4 Pre-Test Check ListEnsure all test equipment is up-to-date and maintainedCheck for vehicle test restrictions and inform consumer if any applyEnsure consumer is provided a proper estimateEnsure vehicle is safeExplain all bullets and their individual requirements.Page 1
5 Vehicle Identification Technician AccessVehicle Identification InformationUsing the bar code scannerUsing vehicle registration documentsVID communication failuresEach tech is responsible the accuracy of the testExplain all bullets and their individual requirements.Page 2 & 3
6 Emissions Tests Before Test Conditions No safety hazards Vehicle is at operating temperatureAll vehicle accessories are offVerify proper test (TSI or ASM)Verify tires are dryVerify vehicle fits on dynoVerify vehicle is restrained properlyPage 5
7 Emissions Tests Before Test Conditions (cont.) Verify cooling fan is positioned correctly (72°)Connect RPM pick-upInsert tailpipe probeLower Hood (ASM)Explain all bullets and their individual requirements.Page 5
8 Emissions Tests Acceleration Simulation Mode (ASM) 50/15 & 25/25 Incompatible vehicle designs“Non-disengagable” traction controlFull time all wheel driveToo large to fit dynoHybrid vehiclesHeavy Duty Vehicles with a drive axle weight that exceeds 5,000 pounds when vehicle is unloadedExplain all bullets and their individual requirements.Page 6
9 Emissions Tests - Preconditioning Vehicle shall be warmed to operating temperature, and idle for at least 3 minutes immediately before starting the emissions testsTechnicians shall not attempt to superheat the catalystRefer to the Smog Check Inspection Procedures Manual, Page 5
10 Emissions Tests ASM Gear Selection TSI Automatic (Drive)Manual (Second gear)TSI2500 RPM for 30 secondsIdle modeRefer to the Smog Check Inspection Procedures Manual, Page 7Explain all bullets and their individual requirements.Page 7
11 BAR Technician Performance Evaluation Bureau of Automotive RepairThis presentation is intended to inform the Smog Check industry of a strategy to evaluate technician performance. BAR plans to evaluate technician performance based on a series of metrics that will be described later in this presentation. The BAR Technician Performance Evaluation will give technicians a grade that they can use to determine how they are performing.
12 Inspection QualityBAR’s strategy to clean the air relies on technicians properly failing those vehicles that should fail. Roadside testing and the Sierra Report both demonstrate that many vehicles that should fail the Smog Check inspection are not being failed appropriately.Fundamentally, in order to clean the air, BAR requires that technicians and stations properly fail vehicles that should fail.Recent data demonstrates that vehicles that should fail the Smog Check inspection are being manipulated so they pass.
13 Inspection QualityWhat are the most common ways to get a failing vehicle to improperly pass an inspection?Not perform required elements of inspection (e.g., timing, fuel cap, LPFET, OBDII)Reset OBDII systems prior to test to clear DTC’sOver-condition ASM test vehicles (restart, abort tests)Drive an ASM inspection in the incorrect gearDirect cheating (clean piping, clean plugging, etc).There are a number of strategies that can be used to get vehicles that should fail their Smog Check to pass instead. One is to not perform a required element of the inspection, such as the timing test, fuel cap test, low-pressure fuel evaporative test and the OBDII test. In these cases, some technicians incorrectly indicate during the test that the vehicle is untestable and then that portion is bypassed.On an OBDII failure, some technicians will reset the OBDII diagnostic trouble codes prior to the inspection. If the code is slow to reset, the vehicle may pass before the code appears again. This is particularly effective when the diagnostic trouble code is related to the evaporative system, as those are typically the slowest codes to re-appear.Properly conditioning the vehicle without superheating the catalyst is important to accurately pass or fail a Smog Check inspection. Some technicians will over-condition vehicles prior to the start of the ASM test to superheat a tired catalytic converter before the test. Note that while there are no applicable limits with respect to preconditioning during the TSI test, aggressive preconditioning is not permitted during the ASM test. To guard against this, technicians should idle vehicles that are already fully warm for at least 3 minutes prior to beginning the ASM test mode. This will bring vehicles to a consistent testable condition.When dealing with a Nox failure, some technicians simply drive the vehicle is a lower gear than directed by the procedures. This tends to lower pressure in the cylinder during combustion and, in turn, lowers the high temperatures which drive NOx formation.Finally, some technicians cheat using methods such as clean piping or clean plugging (where you use another vehicle’s OBDII system as a surrogate for the test vehicle during the test).
14 Inspection QualityTest deviations measure departures from required inspection procedures as appropriate to the vehicleFailing to inspect ignition timingFailing to inspect the fuel capFailing to perform the LPFET testFailing to perform the OBDII testResetting OBDII systems without making repairs to get vehicle to “slip” throughRestarting or Aborting tests to provide second chance (over-conditioning)Using the wrong transmission gear for the ASM testUsing data from the VID (Vehicle Information Database), BAR can determine the accuracy of technician data, based on hundreds of technician entries from the exact same type of vehicle (same year, make, model, engine, transmission and body type).When an entry doesn’t agree with entries from other technicians, based on the exact same type of vehicle (same year, make, model, engine transmission and body type), BAR notes that anomaly as a ‘deviation’.Test deviations accumulate when technicians fail to perform the ignition timing test, the fuel cap test, the low-pressure fuel evaporative test, and the OBDII test. Test deviations also consider the rate at which vehicles pass with exactly the allowed number of unset readiness monitors as an indication of vehicle computer resetting prior to inspection, and also the restart and abort test rates. Lastly, test deviations accumulate based on the frequency that a technician uses the wrong transmission gear when performing an ASM test.We will now take a look at the specific elements of test deviations to discuss how they are measured.
15 Inspection Quality Test Deviations – Ignition Timing Measures the rate at which each station fails to perform a timing inspection when most technicians indicate that the timing is adjustableDeviation flag set when a station’s rate is above average for similar vehiclesIgnition timing within the test deviations considers whether the rate at which a technician fails to inspect ignition timing on vehicles that shouldhave been tested is greater than average for similar vehicles. To measure this, ignition timing test result data from throughout the state are grouped by vehicle similarity. Vehicles are considered similar if they are the same year, make, model, engine, transmission, and body type. Within each group, if at least 90% of the inspections indicate that the vehicle’s ignition timing was testable, then we assume that the vehicle was, in fact, testable. Any time a technician indicates that a vehicle we believe to be testable is untestable, we count it as a deviation.
16 Inspection Quality Test Deviations – Fuel Cap Measures the rate at which each station fails to perform a fuel cap pressure test when most technicians indicate that the fuel cap is testableDeviation flag set when a station’s rate is above average for similar vehiclesLike the ignition timing test, the fuel cap deviation considers whether the rate at which a technician fails to perform the fuel cap pressure test on vehicles that should have been tested is greater than average for similar vehicles. Again, test results from throughout the state are grouped by vehicle similarity; vehicles are considered similar if they are the same year, make, model, engine, transmission and body type.Within each group, if at least 90% of the inspections indicate that the vehicle’s fuel cap was testable, then we assume that the vehicle was, in fact, testable. Any time a technician indicates that a vehicle we believe to be testable is untestable, we count it as a deviation.Note that model year 2000 and newer vehicles are not subject to the fuel cap test and should not be given that portion of the inspection. Accordingly, model year 2000 and newer vehicles are not considered while establishing test deviations for the fuel cap test.
17 Inspection Quality Test Deviations – LPFET Measures the rate at which each station fails to perform the LPFET when most technicians indicate that the vehicle’s evaporative system is testableDeviation flag set when a station’s rate is above average for similar vehiclesThe low-pressure fuel evaporative test follows the same pattern again. Did the technician indicate a vehicle wasn’t testable when at least 90% of other inspections indicate that it was. If so, we count it as a deviation. It’s important to note that comparisons are only made to other vehicles that have the same year, make, model, engine, transmission and body type.
18 Inspection Quality Test Deviations – OBDII Test Measures the rate at which each station fails to perform a OBDII test when most technicians indicate that the vehicle’s OBDII system is testableDeviation flag set when a station’s rate is greater than average for similar vehiclesThe OBDII test again follows the same pattern. Did the technician indicate a vehicle wasn’t testable when at least 90% of other inspections on similar vehicles indicate that it was?
19 Inspection Quality Test Deviations – OBDII Reset Measures the rate at which each station passes vehicles with the exact number of necessary OBDII readiness monitors set in order to passDeviation flag set when a station’s rate is greater than 125% of average for similar vehiclesThe OBDII reset rate deviation differs from the other deviations considered thus far. First-of-all, OBDII resets are not, in and of themselves, a bad thing. After performing a OBDII-related repair, a technician would need to reset the computer to verify that the repairs addressed the underlying problem. Resets do become a problem, however, when technicians gratuitously perform them to mask underlying emissions problems. With this being the case, this deviation considers the rate at which vehicles are inspected with the maximum number of unset readiness monitors allowed to pass an inspection. Model year 2000 and older vehicles are usually allowed up to two unset monitors while most 2001 and newer vehicles are allowed only one.
20 Inspection Quality Test Deviations – ASM Restart Measures the rate at which each station restarts ASM inspectionsDeviation flag set when a station’s rate is greater than 125% of average for similar vehiclesAlong the same lines, ASM restarts are not, in and of themselves, an indication of lower performance. In many cases, tests must be restarted for a number of reasons, including safety concerns or vehicle-related problems. When restarts are performed often, however, this can be an indication of vehicle over-conditioning and even potentially clean-piping.
21 Inspection Quality Test Deviations – Inspection Abort Measures the rate at which each station aborts inspectionsAbort flag set when a station’s rate is greater than 5% of total inspection startsLastly among the test deviations are test aborts. Aborts are similar to restarts in nature in that they can be used to keep vehicles from appropriately failing a Smog Check inspection. Unlike all of the other deviations considered thus far, however, aborts are not considered on a vehicle specific basis, or by model year, make, model, etc. The reason for this is that many inspections are aborted before specific vehicle information is recorded, thus we do not have sufficient information to perform the adjustment.
22 Inspection Quality Improper Gear Selection – ASM test Manual Trans – test in 2nd gear (Page 7, Smog Check Manual)Auto Trans – test in drive (Page 7, Smog Check Manual)Engine RPM during tests indicates when vehicle in incorrect gearRPM limits assigned by specific vehicle configurationExample: 1989 Toyota Camry, 2.5l auto transLimit = 90 percentile rpmStations disqualified if more than 2% of vehicles were certified with RPM beyond limits in either ASM test modeSelecting the proper gear in which to operate the vehicle during an ASM test mode is both easy and clearly spelled out in section of the Smog Check inspection manual, which is available online. Manual transmission vehicles should be driven in second gear. They may only be shifted into another gear if the engine RPM falls outside of the allowable RPM window. Automatic transmission vehicles should be driven in drive. When technicians deviate from these procedures, the engine RPM during the test will usually reflect the change. It is by comparing engine RPM’s for similar vehicles (same year, make, model, engine, transmission and body type) during an ASM test that we can determine if an improper gear selection has been made.In reality, the standard by which the improper gear selection is determined as proposed here is extremely lenient. Recorded engine speeds for similar vehicles for each mode of the ASM test are grouped together. Next, they are sorted from the lowest RPM to the highest. The RPM limit for the vehicle is then established by adding 300 rpm to the 90th percentile reading. In other words, if there were engine speeds from 100 different ASM 5015 test on similar vehicles, they would be sorted from lowest to highest and then 300 rpm would be added to the 90th reading (the 10th highest reading). Any engine speed recorded above this limit would be considered a manifestation of improper gear selection.
23 Inspection Quality Improper gear selection – example of limit This slide shows actual engine RPM data during the 5015 portion of the ASM test for 1989 Toyota Camry, 2.5 liter engine, automatic transmission. As shown, one primary hump comprises the vast majority of inspection data for the vehicle. There is also a small secondary hump, however, that falls to the right of the primary hump. This hump is the result of vehicles being shifted into a lower gear during the test.After initially seeing this distribution, many people have expressed concerns about how well this measure will work when similar vehicles have different available axle ratios, wheel sizes, etc. This is a valid concern, though with the lenient limits herein proposed is not a problem. What usually happens is that the primary distribution won’t be tight like the one shown above, but will spread wider, driving the 90th percentile reading out further along the range. After adding the 300 rpm buffer, only the extreme outliers end up being identified. This will often mean that vehicles that were actually shifted into the incorrect gear won’t be identified as shifted. Thus, this measure will err on the side of leniency.
24 Inspection Quality Improper gear selection example: 1989 Toyota Camry, 2.5l automaticThis slide shows historical data from one of the 1989 Camry’s found in the secondary hump on the previous slide. You can see there are five Smog Check inspections on this car that span a time range from February 2005 to February The next slide provide a close up of the same information.
25 Inspection Quality Improper gear selection example: 1989 Toyota Camry, 2.5l automaticHere is a close-up of data from the previous slide. The oldest test is at the bottom of the slide and the most recent is at the top. If you review the RPM for the older tests, you’ll find the RPM ranges from 1762 to However, in the most recent test shown in the top row, the RPM was at Based upon the historical RPM readings for both the 5015 and 2525 portions of the test, this car was obviously tested in the wrong gear during the 5015 portion of the test. Data like this is typical when reviewing tests identified as having gear selection problems.
26 Inspection QualityComparative Failure Rate (CFR)– serves as a basic litmus test for whether a technician is failing vehicles that should fail.Compares the technician’s failure rate to the industry failure rate for the same type of vehicle.Another metric for evaluating technician performance is the Comparative Failure Rate or CFR. The CFR compares a technician’s failure rate to the industry failure rate for the same type of vehicle (same year, make, model, engine, transmission and body style).However, with the CFR, vehicle similarity is established not just by year, make, model, engine, transmission and body shape. BAR also considers the length of time since the vehicle was last certified, the previous inspection result, and most importantly, the odometer reading of the vehicle. The odometer reading is extremely important as two similar vehicles with dramatically different accumulated miles will have dramatically different expected failure rates.
27 Inspection Quality Comparative Failure Rate The technician’s failure rate must be greater than or equal to 75% of the statewide failure rate for similar vehicles.With respect to setting the standard for performance, it is important to note that expected versus achieved failure rate, by itself, it not necessarily a great indicator of technician performance. Just because a technician’s failure rate is a little below average doesn’t mean that the technician is necessarily doing anything wrong. Still, technicians performing proper inspections should be failing some vehicles. For this reason, technicians are allowed to be somewhat below average and still pass the standard. In short, each technician’s failure rate must be greater than or equal to 75% of the statewide average for similar vehicles tested using the same test (ASM or TSI) and on the same inspection cycle.
28 Inspection QualityWhile the performance metrics discussed thus far will push performance higher, they can be manipulatedExamples – RPM simulators, entering vehicles as testable for certain program elements (e.g., LPFET) and then faking the test results, etc.Solution: Introduce a robust long-term metric to ensure quality over the long haulThe inspection performance measures discussed thus far will, by themselves, tend to improve performance in the Smog Check industry. Still, they are somewhat flawed in that they can be manipulated by unscrupulous technicians and stations. For example, technicians can use an RPM simulator during an ASM test to mask gear shifting.The solution to this problem is to introduce a long term metric that evaluates vehicle performance over the long haul to help assess station performance.
29 Inspection Quality - FPR “Follow-up Pass Rate” (FPR) correlates current cycle pass rates to quality of inspection in the previous cycleComparison made across similar vehicles (Model year, make, model, engine size, transmission type, body shape, time since last inspection, previous inspection result, vehicle odometer)The long-term metric BAR plans to use is called the follow-up pass rate, or FPR.The Follow-Up Pass Rate correlates current cycle pass rates to the quality of inspection in the previous cycle. Like many other measurements, the current cycle pass rates are only compared to similar vehicles based upon year, make, model, engine, transmission, body shape, time since the last inspection, previous inspection result, and the vehicle odometer. In other words, if you only inspect 1976 Chevrolet Chevettes as pictured here, your pass rates would only be compared to the pass rates for other 1976 Chevrolet Chevettes under similar conditions.
30 Inspection Quality - FPR Conceptual example: two hundred L Ford Mustangs were high-emitting vehicles in the last inspection cycle.Half were clean-piped, shifted into the wrong gear, or over-conditioned in order to pass their last inspection.The other half were properly inspected, failed, and then repaired to legitimately pass their last inspection.Vehicles from which group are more likely to pass in the current cycle?To better understand the concept of this metric, consider liter Ford Mustangs in which all were high emitting vehicles in the previous inspection cycle. Half of those vehicles were clean-piped, shifted into the wrong gear, or over-conditioned in order to pass their last inspection. The other half were properly inspected, failed and then repaired to legitimately pass their last inspection. Vehicle from which group are more likely to fail in the current cycle?If you answered that the repaired and properly inspected vehicles were more likely to pass, you are correct, and the results would not even be that close. In other words, improper inspections lead to higher downstream failure rates, while proper inspections lead to lower downstream failure rates.
31 Inspection Quality - FPR FPR scores reflect probability that a technician’s vehicles pass at a higher rate than average in the next inspection cycleScores Range from 0 to 10 score means we are 100% confident that performance is below average1 score means we are 100% confident above average0.5 means we don’t know conclusively due to insufficient test historyNew or low-volume technicians assigned 0.5 scoreBy measuring the current test cycle failure rates as assigned to the inspector that last certified the vehicle, we get robust insight into the quality of the previous inspection.Follow-up Pass Rate scores range from 0 to 1, with 0 meaning that we are 100% confident that the performance is below average (failure rates are above average). A 1 indicates that we are 100% confident that the performance is above average (the failure rate in the current cycle is below average). The vast majority of scores fall toward the middle between 0 and 1.Because the FPR measures performance as a function of who last certified the vehicle, newly minted technicians cannot be evaluated using this metric. Another factor affecting the FPR is the volume of inspections. We need large volumes of test data over which to compare averages. The metrics cannot be calculated with a low volume of test data because spurious test data would be more likely to affect the score. For this reason, both new technicians and technicians with low inspection volumes are cannot be evaluated with this metric. Instead, they are assigned a default score of 0.5, which does not affect them.
32 Technician Feedback BAR will set up a secure Web page to view status. Will provide technicians feedback on their performancePassword protected so technician may view only their own dataTechnicians have requested on multiple occasions, that BAR provide performance feedback. In response to these requests, BAR plans to set up a secure website for technicians to do just that. The site will be password protected so only the technician has access to their performance information.
33 UNDERSTANDING AFTERMARKET PARTS This section is to help understand the process for inspecting and researching the legality of aftermarket parts.
34 Covered TopicsHow to recognize aftermarket parts during a visual inspectionParts labels, Executive Orders (EO) and links to verify partsPre 1/1/2009 catalytic converter labelingPost 1/1/2009 catalytic converter labelingOther approved aftermarket parts examplesModified aftermarket parts examplesSome of the topics covered in this section are;How to recognize aftermarket parts during a visual inspectionParts labels, Executive orders(EO) and links to verify parts.Pre 1/1/2009 Catalytic Converter labeling.Post 1/1/2009 Catalytic Converter labeling.Other approved aftermarket parts examples.Non-Approved EO parts examples.
35 Visual InspectionVehicle Emission Control Requirements: Technicians must use all available information necessary to determine the vehicle’s emission control requirements, including but not limited to:The under-hood emission control label (see section 1.3.2)The current emission control application guideThe emission control repair manualsThe emission component location guidesThe manufacturer emission control recalls and TSB’s (Technical Service Bulletins)The vacuum hose routing diagramsThe California Air Resources Board (CARB) aftermarket parts listings, the aftermarket part label (see section 1.3.2), and any reliable vehicle manufacturer sources.Vehicle Emission Control Requirements: Technicians must use all available information necessary to determine the vehicle’s emission control requirements, including but not limited to:The under-hood emission control label (see section 1.3.2)The current emission control application guideThe emission control repair manualsThe emission component location guidesThe manufacturer emission control recalls and TSB’s(Technical Service Bulletins)The vacuum hose routing diagramsThe California Air Resources Board (CARB) aftermarket parts listings, the aftermarket part label (see section 1.3.2), and any reliable vehicle manufacturer sources.
36 Visual InspectionIf a vehicle is equipped with parts that modify the original emission control configuration, technicians must verify whether those parts are CARB approved or exempted. If the installed parts are not CARB approved or exempted, and the original emissions control configuration has been modified, the corresponding emission controls are considered “Modified” and the vehicle shall fail the inspection
37 Smog Check Reference Guide Aftermarket Parts Verification Guidelines Gasoline and Diesel – Appendix GAftermarket Parts DefinitionsCategory I lists parts that do not require EO verificationCategory II lists parts that require EO verificationDiesel Quick ReferenceThere are a few exceptions to the rule. Make sure you review the Smog check reference manual, under Appendix g for a list of these examples.
38 Visual Inspection(cont.) To verify CARB approval or exemption, technicians must check the Aftermarket Parts Label affixed either directly to the part or near the part. This label contains a CARB Executive Order (EO) number that can be used to verify approval or exemption. With the EO number, reference the CARB EO parts listings and/or part manufacturer catalogThe CARB EO part listings and information about catalytic converters can be found on the CARB website Technicians may also contact ARB at (800) if they need additional informationTo verify CARB approval or exemption, technicians must check the Aftermarket Parts Label affixed either directly to the part or near the part. This label contains a CARB Executive Order (EO) number that can be used to verify approval or exemption. With the EO number, reference the CARB EO parts listings and/or part manufacturer catalog.The CARB EO part listings and information about catalytic converters can be found on the CARB website Technicians may also contact ARB at (800) if they need additional information.
39 Aftermarket Parts Label Note: A missing or illegible APL does not constitute an inspection failure. In cases where the label is missing or illegible, the technician may proceed with the inspection, provided the parts can be confirmed as CARB approved or exempted by comparing the part number marked on the part with the CARB EO parts listings or the parts manufacturer catalogAFTERMARKET PARTS LABELA missing or illegible APL does not constitute an inspection failure. In cases where the label is missing or illegible, the technician may proceed with the inspection, provided the parts can be confirmed as CARB approved or exempted by comparing the part number marked on the part with the CARB EO parts listings or the parts manufacturer catalog.
40 Web Links AFTERMARKET PARTS DATABASE OF EXECUTIVE ORDERS CURRENT LIST OF AFTERMARKET CATALYSTSPRODUCTS IN PROGRESS LIST (DIESEL)LIST OF AFTERMARKET CATALYTIC CONVERTERS IN COMPLIANCE WITH NEW REGULATIONSAPPENDIX G – AFTERMARKET PARTS VERIFICATION GUIDELINESThe web is a excellent tool that should be utilized whenever you have questions about aftermarket parts. You should familiarize yourself with and We suggest you set these websites into your “favorites” for quick reference.
41 Non-Original Equipment Catalytic Converters All Non-original catalytic converters must be CARB approved/exempt and are labeled with information necessary to ensure that installations comply with California law.Aftermarket replacement catalytic converters are labeled with important information necessary to ensure that installations comply with California law.New aftermarket converters produced and sold before January 1, 2009 are labeled according to U.S. EPA requirements. A code in the following format will be stamped or affixed to the shell of the converter.
42 Catalytic Converter Labeling Catalytic converters installed before January 1, 2009New aftermarket catalytic converters and certified used catalytic converters can be identified by a permanent stamp or label on the shell of the converter. The label/stamp should be in the following U.S. E.P.A. format: T/CA/MC XXXX YYYY. The labels do not include the EO numberAFTERMARKET (NON-ORIGINAL EQUIPMENT) CATALYTIC CONVERTERSNon-original equipment catalytic converters (gasoline only - all diesel exhaust gas after treatment systems, including catalysts must meet original equipment specifications).Catalytic converters installed before January 1,2009new aftermarket catalytic converters and certified used catalytic converters can be identified by a permanent stamp or label on the shell of the converter. the label/stamp should be in the following u.s. E.P.A. format:T/CA/MC XXXX YYYY42
43 T/CA/MC XXXX YYYYT: Either “N” (for new aftermarket converters), or “U” (for certified used converters). ARB staff has found that this character is sometimes omitted on new aftermarket convertersCA: Indicates that the converter has been ARB approvedMC: A two character code for the converter manufacturerXXXX: The converter’s part or series number. The number may be longer than 4 digitsYYYY: The date of manufacture. The first two digits indicate the month, and the last two the yearRefer Students to Appendix G page 4.
44 Pre- 1/1/09 Labeling Example TA = ManufacturerSee Website DatabaseCA = ARB Approved in CaliforniaThe Converter Part/Serial NumberManufacture DateMonth/YearN = New AftermarketThis example of a pre-1/1/09 catalyst can be decoded with the indicated meanings.N = new AftermarketCA = ARB Approved in CaliforniaTA = Manufacturer, See Website DatabaseThe Converter Part/Serial Number is indicated as aboveManufacture Date Month/Year 09/05
45 This Table Lists Valid Manufacturer Codes For California ADAdvanced Car Specialties (RiteCat).ESESW America, Inc.AEThe Automotive Edge (Hermoff)ETEmico Technologies, Inc.ATAirTek, Inc. (Catco)LPLaPointe Exhaust System EquipmentBNBrown Recycling & Manufacturing, Inc.MCMiller Catalyzer CorpBOBosal Mexico SA DECVMMMaremontCECar Sound Exhaust System, Inc.(Magnaflow)PAPerfection Auto Prod. CorpCTValina, Inc. (CarTex).PPProducts For PowerCVCateran Pty Ltd.TAWalker ManufacturingEMEastern Manufacturing Inc.TDTRI-D Industries Inc.EQEquipo Industrial Automotriz S.A. de C.V.TPTested Products (DEC)THIS TABLE LISTS VALID MANUFACTURER CODES FOR CALIFORNIA
46 Catalytic Converter Labeling Catalytic converters installed on or after January 1, 2009Meet more stringent requirementsLabels include the EO number in large font, presented in the following format:D-XXX-XXYYYYYYZZZZAfter 1/1/09 the labels will be coded in the following format:D-XXX-XXYYYYYYZZZZ
47 Decoding Catalyst Labels D-XXX-XX =This is the ARB approval number for the converter (known as the “EO number”). Every EO number will begin with “D”. The first three X’s will be a 3 digit number corresponding to the manufacturer. The last two digits will be the specific approval number for the manufacturer. The EO number can be used to obtain information about the approval status of the converter on ARB’s website in the same manner that other aftermarket add-on and performance parts can be looked up. The website address is:DECODING CATALYST LABELSThe first code is the ARB approval number for the converter (known as the “EO number”). Every EO number will begin with “D”. The first three X’s will be a 3 digit number corresponding to the manufacturer. The last two digits will be the specific approval number for the manufacturer. The EO number can be used to obtain information about the approval status of the converter on ARB’s website in the same manner that other aftermarket add-on and performance parts can be looked up.The second code is the part number for the converter (assigned by the manufacturer)The third code is the date of manufacture. The first two digits indicate the month, and the last two the year.YYYYYY =The part number for the converter (assigned by the manufacturer)ZZZZ =The date of manufacture. The first two digits indicate the month, and the last two the year.
48 Legal Converters With Laser Printing And Plate ID CONVERTER WITH LASER PRINTINGSEE EO#DThis slide shows two examples of printing and codes on aftermarket post 1/1/09 catalysts.Top example is a CONVERTER WITH LASER PRINTING, SEE EO# DThe lower example is a CONVERTER WITH PLATE ID, SEE EO# DCONVERTER WITH PLATE IDSEE EO#D
49 Manufacturer Assigned part # 36104 Labeling ExampleManufacturer Assigned part # 36104ARB EO# DAnother labeling example. Again, post 1/1/09Refer to Catalytic converter article about proper replacement position and that converters must be replaced one for one.Manufactured March 200903/09
50 Resource ExamplesThis screenshot shows where to enter the replacement part EO number into the ARB search engine.Enter the EO# here: DLeft Click HereThis is a screenshot is directly from the ARB website showing the search engine for EO numbers. Or search by EO or Manufacturer for the device type.
51 EO # D-193-86 Entered Into ARB Search Engine Screenshot showing the results of the previous slides EO#.
52 A FEW EXAMPLES OF OTHER APPROVED AFTERMARKET PARTS
53 Fuel Injection Conversion Kit With EO - 1979 Jeep Cherokee CARB EO# D452-2Example of EO label
54 1979 Jeep Carburetor is replaced with a TBI unit This ‘79 Jeep TBI(Throttle body injection) is approved
55 Aftermarket Air Intake with EO - 2003 Mitsubishi Eclipse AFTERMARKET AIR INTAKE SYSTEMThis approved intake has a visible sticker at the end of the arrow.
56 2003 Eclipse EO Sticker Attached Underhood To Vehicle Body The CARB# is D and will beThis is just one example of many CARB approved aftermarket parts.
57 Then Scrolling Down On The EO Page We Find That The Vehicle And Engine Are LISTED. IF POSSIBLE, MATCH A PART NUMBER WITH THE PART. THIS AIR INTAKE SYSTEM WOULD BE A PASS ON THIS VEHICLE.Screenshot indicates that the EO part# matches the vehicle. This would be a pass in EIS.
58 SOME EXAMPLES OF “MODIFIED” AFTERMARKET PARTS This sections shows some examples of non-approved smog devises.
59 Adjustable Cam Gears Cam gears with complete adjustment possibilities. Technicians are not expected to remove timing covers to inspect cam gears.
60 Aftermarket Headers With No EO 1995 Saturn Sl 1.9L Saturn exhaust headers
61 Aftermarket Air Intake With No EO 2003 Toyota Celica Toyota intake system
62 Aftermarket Air Intake With No EO 99 Honda Civic Aftermarket air intake system- no EOHonda intake system
63 What to enter into the EIS? The Other Emissions Related Components category encompasses emission control systems that are not otherwise addressed in the visual inspection menu. Other Emission Related Components include, but are not limited to: Add-On Aftermarket PartsCylinder HeadsExhaust ManifoldsIntake ManifoldsSuperchargersThermal ReactorsTiming Gears and PulleysTurbochargers
64 Other Emissions Related Components If a vehicle fails the Other Emissions Related Components category of the visual inspection, technicians must document, on the VIR, what emissions system failed.Note: The Other Emissions Related Components field is also used to capture failed test results for the Visible Smoke Test. For more information, see Smog Check Inspection Manual section
65 Notations on the repair order It is necessary to make notations on the repair order of any aftermarket devices that are entered into the EIS “other” category.If there is no Executive Order (EO), enter as “Modified”.
66 California Code of Regulations 3340.41 (a) Test Report Requirements(b) EIS Access & Tampering(c) Entering Information into the EIS(d) Repair Procedures(e) Testing Directed VehiclesCover CCR thoroughly and its importance that technicians understand that it covers the proper testing and repair of all vehicles under the Smog Check Program
78 Understanding Sensors The Powertrain Control Module (PCM) performs two distinctive functionsPerforms Voltage Drop TestsPerforms Logical Decisions based on the voltage drop test results.Remember that the PCM uses inputs to make decisions and control outputs
79 Sensors There are three categories of sensors; Variable Resistance Has an internal resistor, the resistance value changes with Temperature, Pressure, Air Flow or PositionVoltage ProducingProduce voltage based on engine detonation/pinging, oxygen content of the exhaust, rotation of the Crankshaft, Camshaft, Wheels or Vehicle SpeedSwitching TypeA switch type sensor input is a clear high or low signal, depending on whether the switch is open or closedSee page 11.
80 Types of Sensor Signals Analog SignalsA variable signal that is proportional to a measured quantity.Analog signals are produced by sensors that mechanically change resistance to deliver variable voltage signals. Analog signals are produced by variable resistance type sensors and voltage producing type sensorsAnalog – A variable signal that is proportional to a measured quantity.See page 12.
81 Types of Sensor Signals Digital SignalDigital signals are On – Off voltage pulses, typically 2.5, 5.0 or 12 volts.AC voltage generating sensor signals are converted into digital signals. This conversion process takes place by an Analog / Digital Converter.Digital – An On (High) or Off (Low) voltage pulseSee page 12.
82 Types of SensorsHall Effect – Monitors the speed of a rotating component. Permanent Magnet – Monitors the speed of a rotating componentPressure – Monitors pressure within a component or system.Position – Monitors the position of a component.Thermistors – Measure temperature within a component or systemBrief description of the various types of sensors.You can give brief examples of the uses for the different typesSee page 13.
83 Hall Effect SensorsAre frequently used where accuracy and fast response are importantContain a powerful magnet, as the magnet passes over a dense portion of the trigger wheel the 5 volts is pulled to ground (.3V) through a transistor in the sensor, when the magnet passes over a notch in the trigger wheel the 5 volts is restored.See page 13.
84 Types of Hall Effect Sensors used on today’s automobiles are: Cam Position Sensors (CMP Sensors)Crankshaft Position Sensors (CKP Sensors)Hall Effect sensors contain a powerful magnet, as the magnet passes over a dense portion of the trigger wheel the 5 volts is pulled to ground (.3V) through a transistor in the sensor, when the magnet passes over a notch in the trigger wheel the 5 volts is restoredSee page 13.5 Volts0 Volts
85 Permanent Magnet Sensors Consists of a permanent magnet surrounded by a winding of wireWhen a metallic (iron or steel) is passed extremely close the magnet, the magnetic field is interrupted and a small amount of AC voltage is induced into the windingsThe induced AC voltage amount varies by:Speed of interruptionDistance between magnet and metallic object andStrength of magnet.See page 14
86 Permanent Magnet Sensors Surrounded with wirePermanent Magnet SensorReluctor Wheel attached to CrankshaftSignal from fast interruption of magnetic fieldSignal from slow interruption of magnetic fieldTypes of Permanent Magnet sensors used on today’s automobiles are:Cam Position Sensors (CMP Sensors)Crankshaft Position Sensors (CKP Sensors)Wheel Speed Sensors (WSS Sensors)Vehicle Speed Sensors (VSS Sensors)Transmission Input & Output Speed SensorsSee page 14
87 Pressure Sensors and Switches Atmospheric pressure is 14.7 PSI or sea levelPressure sensors monitor the pressure differential between atmospheric pressure and the pressure within a component or systemPressure sensors also monitor barometric pressure (atmospheric pressure)Pressure sensors are three wire sensors; a three wire sensor has a reference voltage wire (vref) from the PCM, a ground and a signal voltage wirePressure Switches are typically a two-wire “on/off” switch located in a location where fluid pressure monitoring is criticalSee page 15
88 Pressure Sensors and Switches Types of Pressure sensors used on today’s automobiles are:Manifold Absolute Pressure Sensor (MAP Sensor)Fuel Tank Pressure Sensor (FTP Sensor)Barometric Pressure Sensor (Baro Sensor)Delta Pressure Feedback EGR Sensor (DPFE Sensor)See handout for description of outputSee page 16
89 Intake Air Flow Sensors Two ways to measure intake airflowSpeed DensityMeasures intake air flow by sensing changes in intake manifold pressure using a pressure type sensorMass AirflowMeasures the volume, density and on some the temperature of the incoming air using a vane type or hot wire type sensorSee page 17
90 Flap – Type or Vain Air Flow Meter Vane Air Flow SensorUtilizes an air flow door (flap) connected to a potentiometerFlap – Type or Vain Air Flow MeterSee page 17
91 Hot Wire Air Flow Sensor The most common type of Mass Airflow Sensor (MAF)All hot wire type sensors use the same operating principleSee page 18
92 Hot Wire Air Flow Sensor Incorporates a small orifice inside the main body, as air passes through the MAF a steady flow also passes through a small orificeInside there are two wires, a compensating wire and a sensing wire.See page 18
93 Hot Wire Air Flow Sensor Compensating Wire The compensating wire is a thermistor that has a small amount of current passing through it.As the volume of air increases “cooling the thermistor” the resistance (Voltage) of the thermistor increases.The voltage represents the temperature of incoming air.See page 18
94 Hot Wire Air Flow Sensor Sensing Wire The sensing wire is maintained at a constant temperature, approx 170° to 212°F (depending on manufacturer) above the temperature of the compensating wireThis temperature is maintained by varying the current flowing through itSee page 18
95 Hot Wire Air Flow Sensor As air flow increases, current increasesAs air flow decreases, current decreasesThe amount of current flow = amount of air flowAirAir=AmpsAmpsSee page 18
96 Position SensorsProvide linear or angular measurement in relation to the position of that specific item or component . There are two types of position measuring sensors they are:RheostatPotentiometerSee page 19
97 Rheostat Is a two wire sensor Fuel GaugeRheostatIGNGRDIs a two wire sensorMost common uses of the rheostat is for the Fuel Level SenderSee page 19
98 Potentiometer Most common type of position sensor Contains a mechanical arm that is attached a moving component (throttle plate, accelerator pedal, airflow door, etc.) which causes it to slide across a fixed resistor within the sensorSee page 19
99 Potentiometer The potentiometer functions as a voltage divider. GroundReference VoltageSignal ReturnThe potentiometer functions as a voltage divider.See page 19As position increases, the arm moves to a higher resistance portion of the resistor causing the voltage on the return line to increase and the opposite is also true.
100 Thermistors Thermal resistors are used for sensing temperature Two basic types of thermistors:Positive Thermal Coefficient (PTC)Negative Thermal Coefficient (NTC)Most common type used for sensing air temperature and fluid temperaturesSee page 20
101 Positive Thermal Coefficient (PTC) Temperature and resistance (Voltage) are directly proportionalNote how resistance and temperature follow each other in the animation.See page 20
102 Negative Thermal Coefficient (NTC) Temperature and resistance (Voltage) are inversely proportionalNote how resistance and temperature follow each other in the animationSee page 20
103 Oxygen Detecting Sensors Located in the exhaust stream and provides feedback information to the PCM about the oxygen content in the exhaustGenerates its own voltage signalThere are three types of oxygen sensorsZirconiumTitaniaAir Fuel RatioMost common sensor is the Zirconium sensorSee page 21
104 Oxygen Sensor Construction Has a center element made of a ceramic material called zirconiumTwo platinum electrodes make up the inner and outer surfaces of the center elementInternal temperature must be kept above 600⁰FThis is describing the construction of the Zirconium type sensorThe inner surface is the positiveThe outer surface is the negativeSingle wire relies on the exhaust, 2, 3 and 4 wire sensors use heatersSee page 22
105 O2S Voltage Generation O2 sensor operation Rich Lean Remember voltage is the potential difference between positive and negative atoms and is the force behind the flow of electrons.When the exhaust gas contains elevated levels of CO, the O2 from the outside air in the inner surface loses some of its electrons to the CO on the outer surface. Heat (600°F) frees the electrons from the oxygen atoms, the zirconium and platinum plates provides conductivity thus allowing the free electrons to flow.A lean mixture (high exhaust oxygen content) contains negative atoms, therefore the two negative atoms would repel; low voltage produced. (The figure on the left).A rich mixture (low exhaust oxygen content) contains positive atoms, therefore the negative atom from the outside air would attract to the positive atom; up to 1 volt will be created. (The figure on the right)See page 23
106 Air Fuel Ratio SensorsThey perform the same function as zirconium O2 sensors with some added benefitsAllow a more accurate fuel control over a much wider range (10.1 – 20.1 A/F Ratio)Operational within 10 seconds from a cold start, thereby reducing cold start emissions.Inform the PCM exactly how rich or lean the A/F ratio isAir fuel ratio sensors also have several names-Broad Planar O2 Sensors-Wide Band O2 Sensors-Lean Air Fuel Ratio Sensors-Air Fuel Ratio SensorsIt has 2 o2 sensors in one housingSee page 24
107 A/F Sensor Construction Exhaust GuardCeramic Seal AssemblySensor HousingCeramic Support TubePlanar Sensor ElementProtective CapSensor WiresBasic Construction of the sensor casingThe planar element is the internal workingsSee page 24
108 Planar Sensor ElementThe air fuel ratio sensor contain two zirconium O2 sensors, one to measure the oxygen content of the exhaust (zirconium Sense Cell) and another zirconium O2 sensor (zirconium pump cell) to control the zirconium sense cell. Also contains a heater element.Zirconium Pump Cell – Moves oxygen atoms from the exhaust gas chamber to the exhaust sense chamber and from the exhaust sense chamber to the exhaust gas chamber.Exhaust Sense Chamber – Houses a sample of the actual exhaust.Zirconia Sense Cell – measures the oxygen content of the sampled exhaust.Reference Chamber – Houses a sample of outside air for measurement of exhaust oxygen contentThe A/F ratio sensor heater is pulse width modulated (PWM) and is used to keep the sensor around 1200ºSee page 24
109 Planar Sensor ElementThe PCM monitors the exhaust in the exhaust sense chamber, using the zirconium sense cell. (High or Low oxygen content)The PCM will either add or remove oxygen atoms to or from the exhaust sense chamber to keep the sense cell at lambda of 1 (14.7.1). This is accomplished by reversing the polarity of the voltage to the zirconium pump cell.Higher than 450mv – Oxygen is addedLower than 450mv – Oxygen is removedThe amount of oxygen added or removed informs the PCM exactly how rich or lean the A/F ratio is.The zirconium sense cell is a conventional O2 sensor that monitors the oxygen content of the exhaust in the exhaust sense chamber, if the mixture is rich (low oxygen content) above 450mv, the PCM will add oxygen atom to lean out the mixture until the measured voltage equals 450mv. If the mixture is lean (high oxygen content) below 450mv, the PCM will remove oxygen from the exhaust sense chamber until the measure voltage equals 450mvSee page 25
110 Piezoelectric Sensors The knock sensor is a piezoelectric sensorDetects vibrations arising from combustion knock caused by low octane fuel, high engine temperatures, detonation and or pingingAllows the PCM to control ignition timing for the best possible performance while protecting it from potentially damaging detonationA piezoelectric sensor is a device that contains a small ceramic disc that produces a small electric current when it is compressed and then relaxed (vibrates)allows the PCM to control ignition timing for the best possible performance while protecting it from potentially damaging detonationWhen spark knock is detected, the PCM will retard the timing until the knock has ceased, at this point the PCM will advance the ignition timing in steps, back to its normal setting. This allows the engine to operate at peak performance and most advance timing at all timesSee page 27
112 Operating Parameters Sensed Output Components Controlled Outputs / ActuatorsOperating Parameters SensedMAF SensorMAP SensorECT SensorIAT SensorCKP SensorCMP Sensors 1 and 2TP Sensors 1 and 2APP Sensors 1 and 2EGR Valve Position SensorKnock SensorHO2S 1/1, 2/1 and ½PSP SwitchBPP SwitchAC On/Off RequestAC Pressure SensorFuel Level SensorFuel Tank (EVAP) SensorVSS SensorTrans Fluid Temperature SensorTurbine Speed SensorTrans Range SwitchOutput Components ControlledFan Control RelayFuel Pump RelayAC Clutch RelayThrottle Actuator Control MotorMalfunction Indicator LampCamshaft Position SolenoidsEGR ValveFuel InjectorsIgnition CoilsGenerator FieldEVAP Canister Purge SolenoidEVAP Canister Vent SolenoidTorque Converter Clutch SolenoidTrans Pressure Control SolenoidTrans Shift SolenoidPowertrain Control Module(PCM)Using information from various sensors and switches throughout the vehicle, the ECM makes the necessary calculations and then issues operating commands (output signals) to actuators to maintain this stoichiometric air/fuel mixture as well as maintaining optimum vehicle performance throughout the vehicles driving conditions and system operating modes including:Starting ModeClear Flood ModeRun Mode: Open and Closed LoopAcceleration Enrichment ModeDeceleration Enrichment Mode andFuel Cut-Off ModeSee page 28.
113 Types of Outputs/Actuators Actuators are devices that perform work, such as:MotorsStepper MotorsRelaysSolenoidsCoilsLampsGive brief examples of the different uses of the listed devicesFor example Lamp = Malfunction indicator lampSee page 28.
114 Output ControlsThese devices are controlled by the PCM simply by turning them “On” and “Off”, often by providing and removing groundPCMSuppliesGroundSome manufactures use a positive signal to control an actuatorSee page 29
115 Output ControlsThere are several types of output signals from the PCM to control actuators; they are:FrequencySimple ON and Off switch type signalDuty Cycle type signalPulse Width Modulated type signalRemember these are all ways to control “on” timeSee page 29
116 FrequencyFrequency is a measurement of how many times a pattern repeats itself in one secondMeasured in Hertz (Hz)Frequency is measured from the beginning of a pattern to the beginning of the nextOffOnThe higher the frequency the relatively longer the actuator is turned on.The lower the frequency the relatively less the actuator is turned on.See page 30
117 Simple Off and On Actuator is either completely turned on or off Off These types of signals are the most basic form of control by the PCMSee page 30
118 Duty CycleDuty Cycle is the measurement of time an actuator is turned on versus the amount of time it is turned offMeasured in Percentage (%)it’s important to note that the frequency is constant, what varies is the percentage of “On” time.50% ON / 50% OFF = 50% Duty Cycle75% ON / 25% OFF = 75% Duty Cycleparticularly used when the PCM wants to regulate the opening of a solenoid, stepper motor or speed of a motorSee page 30
119 Duty CycleThe measurement of duty cycle is the amount of frequency divided by the “On Time”. Using the example below; the frequency is 12.5Hz, the amount of time the lamp is “On” 50.0Hz (12.5Hz ÷ 50.0Hz = 25% Duty Cycle)See page 31
120 Pulse Width Modulation Pulse refers to turning an actuator on and offWidth refers to the amount of time the actuator is “On”Modulation refers to the fact that the actuator is being controlled, or modulated, over a period of timePulse Width Modulation (PWM) is different from Duty Cycle in that both frequency and On time varies. Duty Cycle signal frequency never changesSee page 31
121 Pulse Width Modulation Example, the Fuel Injector is turned on once per engine cycle, however as the engine RPM’s increase so does the frequency of turning the injector on and off. In the following illustration, the injector is turned on for 6.85ms and 146 times in one second (146.1Hz)Pulse WidthSee page 31
122 Actuators (Load Devices) Most actuators rely on the principles of electromagnetismRelays, Fuel Injectors, Solenoids, and Motors are examples of actuators that utilize electromagnetism for their operationAn electromagnet is an object that acts like a magnet, but its magnetic force is created and controlled by electricity—thus the name electromagnetBy wrapping insulated wire around a piece of iron and then running electrical current through the wire, the iron becomes magnetized. This happens because a magnetic field is created around a wire when it has electrical current running through it. Creating a coil of wire concentrates the field. Wrapping the wire around an iron core greatly increases the strength of the magnetic fieldSee page 32
123 MotorsMost DC (Direct Current) motors contain four main electrical componentsCommutatorConsists of two electrical contacts that are connected to the windings of the armatureBrushes (Contacts)Brushes are mounted in a position that allows contact with the commutator and are the means by which the electromagnet receives voltageArmatureConsists of the electromagnet and a shaft on which the electromagnet is mounted. It is also referred to as a rotorPermanent MagnetThe armature consists of the electromagnet and a shaft on which the electromagnet is mounted. It is also referred to as a rotor. The armature is positioned so that the electromagnet is mounted between the poles of the permanent magnet. The commutator is a device that is mounted on the armature. The commutator consists of two electrical contacts that are connected to the windings of the armature. Two brushes are mounted in a position that allows contact with the commutator. The brushes are connected in series with the motors voltage source, and are the means by which the electromagnet receives voltage.The direction or speed that the motor turns is also varied by switch voltage polarity or by duty cycling the voltage appliedSee page 33
124 Stepper MotorA stepper motor functions similar to a DC motor, however the stepper motor is much more precise in its movementCommon type of stepper motor is the Idle Air Control Valve (IAC)A common form of stepper motors uses two sets of electromagnets and a permanent magnet. Current in one set of electromagnet drives the motor forward and when this is switch off and current is supplied to the second set of electromagnets the motor rotates in the opposite direction (reverse).The most common type of stepper motor is the Idle Air Control Valve (IAC) used on electronically fuel injected engines to control the airflow around the throttle plate when the vehicle is at idleSee page 34
125 RelaysA relay is an electromechanical device that utilizes a small amount of current to energize an electromagnet that closes the contacts in a circuit carrying a higher amount of currentIn the illustration, the PCM supplies ground to point (b) through pin 14, 15, or 16. The ground completes the circuit to the electromagnet, thus creating an electromagnetic field, this magnetic effect pulls an armature toward itself causing a set of contacts to close (point c and d). Once the contacts are closed a higher amount of current is allowed to flow through thus activating the Fuel Pump, AC Clutch and or the Radiator FanSee page 34
126 Transmission Pressure Control Solenoid SolenoidsSolenoids are used to control the mechanical operation of a component, or act as a valve to control gas or fluid flowTransmission Pressure Control SolenoidElectronic ExhaustGas RecirculationValve (EGR)Fuel InjectorsWhen current is supplied, an electromagnetic field is created which draws the armature into itself. The armature also contains a spring that allows the armature to return to its original position when de-energized. The combination of magnetic force, in one direction versus spring force in the other direction allows the solenoid to accomplish linear motion (movement in a straight line). A trunk release solenoid operates in this manner.For a solenoid to function as a valve, it must have a slightly different configuration. The armature works more like a plunger. It has a tip that, when closed a passage is sealed. When the solenoid is energized, it pulls the armature in, and allows the orifice to open and the fluid or gas to pass through. Through PWM (pulse width modulation) the solenoid is able to allow a specific amount of gas or fluid to pass through. A fuel injector is an example of a solenoid functioning as a valve.See page 35
127 Ignition CoilsSecondary WindingsPrimary WindingsPrimary ControlSwitchThe Coil is part of both the primary and secondary circuitWhen the primary ground controlled switch (points, transistor or igniter) is closed, current passing through the primary winding creates a magnetic field. When the switch opens, the magnetic field collapses and secondary voltage is “induced” in the secondary winding then flows through the series circuit containing the spark plug. The voltage jumps the gap between the spark plug’s electrodes and completes the path to ground through the engine blockThe Principle of Mutual InductionA current flow through a primary coil winding produces a magnetic field through a second coil winding, wound around a common steel core. When the primary coil current is shut off, the magnetic field collapses and current is “induced” in the secondary windingsSee page 36
128 LAMPSA lamp contains a resistor called a filament that emits light when current flowing through itThe other type of lamp source is the LED (Light Emitting Diode), LED is a semiconductor light source that is mainly used as indicators, and in the automobile the MIL (Malfunction Indicator Lamp)See page 36
130 OBD II General Diagnostic Strategies The following are eight steps to follow as a suggested Diagnostic Strategy:Verify the customer’s concernCheck the basicsCheck for diagnostic trouble codesCheck and record freeze frame dataCheck PID Data and Monitor StatusReview Repair History and TSBsPerform RepairsVerify RepairsReview the 8 Steps. Refer to real-world situations and case scenariosSee page
131 Verify The Customer’s Concern Obtain as much information as possible from the customerWhen did it start to occur?When does the condition occur?Where does the condition occur?How long does the condition last?How often does the condition occur?Have any repairs been done recently?Are there aftermarket accessories on the vehicle?Establish a Baseline of the vehicle’s conditions, symptoms, and abnormal operationSee page 39
132 Check The BasicsMechanical systems, engine, transmission, induction, exhaust and ignition systems, vacuum lines/hoses, fluid levels and condition, etc.Battery, Starting, and Charging circuits for proper operation, voltages, and voltage dropsSensors & actuators, and computer groundsSteady and reliable reference voltage at all sensorsUnplug suspect sensors with KOEO, and look for related PID values to changeCompare possible PCM-default calculated values to actual sensor voltage valuesSee page 39
133 Review Repair History and TSBs Check for related TSBs for Service Procedure updates, as well as possible computer reprogrammingUse other sources for specific service information either in print or electronicallyKeep accurate repair-related recordsDiagnostics sequenceRecord trouble codesSee page 41
134 Diagnostic Trouble Codes Check for pending codes that may indicate a developing problemCheck for codes stored in memory, even though the MIL may be OFFCheck the exact definition of each codeCheck the enabling criteria needed to run the monitor and set the codeSee page 39
135 Freeze FrameLook at the data and make an accurate record of the exact data that is displayedThe data may not always send you to the exact problem, but it can send you to the area of the problemExample #1: P0300Example #2: If a P0402 excessive EGR flow code is stored, the vehicle runs OK, and Freeze Frame looks normal, check the EGR system. “Good” Freeze Frame data is just as valuable as “Bad” data. The OBD II system sensed a problem, but a component in the system may not be “out of range” enough to set a specific DTC.Example #3: If a P03XX specific cylinder(s) misfire code that was stored under a high load and low RPM condition, and Fuel Trim looks good, check the ignition system. These conditions may indicate a rapid throttle opening during a loaded acceleration from a standing stop or low vehicle speed—exact conditions when ignition-related misfires occur.Possible time for classroom labSee page 39
136 Example #1 A P0300 misfire code is stored LTFT is over +30% Engine is misfiring (lean)System is trying to add fuelCheck fuel pressurePossible causesRestricted fuel filterWeak fuel pumpClogged injectors, etc.Vacuum LeakClassroom discussionSee page 40
137 Example #2 A P0402 excessive EGR flow code is stored Vehicle runs OK Freeze Frame looks normalCheck the EGR system.“Good” Freeze Frame data is just as valuable as “Bad” data.The OBD II system sensed a problem, but no component in the system was “out of range” enough to set a DTCClassroom discussionSee page 40
138 Example #3 A P03XX specific cylinder(s) misfire code that was stored Under a high load at low RPM conditionFuel Trim is normalCheck the ignition systemClassroom discussionSee page 40These conditions indicate a rapid throttle opening during a loaded acceleration from a standing stop or low vehicle speed—exact conditions when ignition-related misfires occur.
139 PID Data and Monitor Status Select the inputs & outputs to be monitored. Too many PIDs slows the update rate of the scan tool.Take a “Snapshot” of the data while the engine is running or while driving the vehicle.Look carefully at the inputs & outputs and their values.Evaluate the information and compare PIDs one to another.Do MAP and BARO agree with the Key On Engine Off (KOEO), and are they logical when the engine is running?Are IAT and ECT the same when the engine is cold and KOEO?See page 40
140 Set your scanner up for PID comparison IAT / ECT ComparisonSet your scanner up for PID comparisonEngine Cold for accurate test results.Compare Coolant Temp with Intake Air Temp.ECT and IAT should be within manufacturer’s specifications.See page 40
141 PID Data and Monitor Status Check battery voltage at KOEO and KOERAre IAC counts normal?Review “Snapshot” data for unusual trendsEstablish a Baseline of the vehicleFreeze Frame and Monitor Status establish a “Before” picture of the vehicle to compare “After” any repairsKeep your information simple but effective—Concentrate on critical PIDsSee page 41
142 Perform RepairsUse the information gathered from the first six steps to assist you with your final diagnosis and repairUse the appropriate tools and equipment that are available to today’s technician to diagnose and repair the modern OBD II vehicleSee page 41
143 Verify RepairsDrive the vehicle until the specific monitor(s) run to completionRunning the monitor(s) allows the system(s) to test themselvesOnce the monitor(s) run to completion, you can either use Mode $06 Data and/or check for current or pending DTCs to assist in verifying your repair(s)If the customer drives the vehicle, the technician is more apt to get a comeback.See page 41If the customer drives the vehicle to run the monitor(s), make them aware they are performing the drive cycle.Make them aware that the OBD II system is designed to test itself as they drive.
145 Fuel TrimThe fuel trim values are very important, so they are included in Freeze Frame data.The data is shown as a percentage, either positive or negative, with 0% being neutral.Greater than 0% means that the system is adding fuel, while less than 0% means that the system is subtracting fuel.The OBD II system closely monitors fuel trim correctionsSee page
146 Fuel TrimOne of the most basic fuel system diagnostic procedures is to determine if the engine control system is operating in open or closed loop.Whatever the HO2S sensor does, the fuel trim corrects.For example, if the HO2S is sensing a lean condition, the STFT will begin to add fuel. As the STFT adds fuel, the LTFT will add fuel in order to lower the STFT.If there is a critical imbalance in the air-to-fuel ratio, the system will store a DTC and illuminate the MIL.Comparing fuel trim from bank-to-bank will allow you to identify a problem that either affects both banks, or if it is isolated in one bank.The voltage signal from the HO2S sensor is the primary indication of loop status, both to the vehicle PCM and to the technicianSee page
147 Fuel TrimThe STFT is a short-term adaptive strategy, which means that it constantly changes based on current operating conditions, and keeps the engine near the best overall air-to-fuel ratio for the vehicle (typically 14.7:1 for most gasoline engines).It also maintains the proper switching from lean-to-rich and rich-to-lean thresholds for proper operation of the CAT.Once the engine is started, they basically start at 0%, and quickly change based on operating conditions and LTFT values, which are stored in the PCM ‘Keep Alive Memory’ (KAM).Refer to example in book on pages 42 – 43.See pageThe STFT values are volatile, meaning they are erased every time the ignition key is switched off.The LTFT values are a ‘long-term adaptive’ strategy, which means that it changes based off of STFT, and will adjust to changes based off of all operating conditions over a period of time, such as wear and tear on the engine and its subsystems
148 Fuel TrimAs the PCM determines that STFT and LTFT are at their maximum values and an air-to-fuel ratio imbalance exists (such as a vacuum leak or leaking injector), it will store a fuel trim related DTC.After establishing the loop status of the vehicle, evaluate the scan tool data, along with a five-gas analyzer, to determine if the PCM is providing a rich or lean correction, and the extent of any such correction.The STFT makes constant adjustments in closed loop status to maintain the ideal air-to-fuel ratio (14.7:1 for most gasoline engines), as well as to allow the proper operation of the CAT.Determining these basic conditions of fuel control system operation is one of the first steps in diagnosing the fuel subsystem (and other related systems) of the entire engine control systemSee page 42 – 43.Relate fuel trim to Lambda
150 Scan ToolData transmitted to the scan tool (PIDs) from the PCM include both digital and analog parameters.Digital parameters are often called ‘switch signals’, and are either on or off, low or high, or yes or no.Analog parameters are often called ‘modified signals’, and are values within a specific minimum-to-maximum rangeThe majority of the scan tool-based training for this course is based off of the ASE L1 Composite Vehicle #3. However, a brief introductory-based section does include an overall view of the proper use of any and all OBD II-related scan tools available to today’s automotive technician.See page 44
151 Scan ToolVoltage readings, speed signals, and temperature readings are just a few examples of PID data.All PIDs transmitted from the PCM to the scan tool has a specific value or signal range described in vehicle specifications.Knowledge of these PIDs specifications is needed during comparison to the scan tool readings to identify a system fault.Other important scan tool Data is also needed in order to validate Enable Criteria for any and all relevant Trip and/or Drive Cycle information to determine System Condition(s), as well as to verify Repair Effectiveness (i.e. Mode $06 through Mode $10).See page
152 Scan ToolScan tool readings that identify an open or a short circuit are among the easiest to recognize.For example, if a resistive sensor is displayed on a scan tool at or near the 5-volt reference voltage, the sensor circuit to the PCM may be open.If, however, the displayed value is at or near 0-volts, the circuit may be groundedA scan tool is a test computer that communicates with the PCM of the modern automobile.The scan tool reads and displays diagnostic information provided by the PCM such as DTCs, PIDs, MIL and Monitor Status, etc.See page
153 Scan ToolThe PCM receives an analog or digital voltages from the input sensors.The PCM processes these signals, and sends a voltage signal or ground to output actuators.The scan tool displays these values (PID).Sometimes the scan tool displays a substitute value to compensate for a failed sensor.See page 45
154 Scan ToolThe substitute or default value is based on pre-programmed OEM engineering software.A sensor failure may cause the PCM to ignore the signal from the failed sensor and operate on ‘substitute’ values stored in its memory.The PCM may transmit the ‘substitute’ values to the scan tool in place of the failed sensor signal.Therefore, if any scan tool data reading does not make sense in relation to a particular problem or symptom, always test the system component directly with a voltmeter, ohmmeter, or oscilloscope to get actual circuit values such as volts, ohms, amps, duty cycle, frequency, pulse width, etc.The serial data stream transmitted from the PCM to the scan tool may have a data list of more than 60 PIDs.Not all of the PIDs are relevant to a single problem or symptom.See page 45The technician is responsible for determining if substitution is displayed.
155 Scan ToolFor general powertrain control diagnosis, the following data parameters are among the most important:System VoltageEngine SpeedEngine LoadVehicle SpeedTemperaturePressureSystem Voltage: The battery and starting system must provide a continuous regulated voltage of 12 to 14 volts. More importantly, the PCM must receive this voltage. Most serial data streams provide a reading of system voltage at the PCM. It must be within the normal range for the PCM and all system components to operate correctly.Engine Speed: The engine RPM, or ‘tach signal’, is the single most important input to the PCM. Without this signal, the PCM cannot determine if the engine is running or not. In fact, it is the only input data parameter that does not have a ‘default’ value. This signal tells the PCM whether the engine is cranking, idling, accelerating, decelerating, or cruising. The ‘tach signal’ affects all ignition, fuel, and transmission control operations of the PCM.Engine Load: Along with RPM, the amount of air entering the engine is a vital input to the PCM. Engine speed and engine load are used to calculate the basic ignition timing and basic fuel delivery for the engine. All other relevant inputs modify these values for other operating modes, such as start-up, cold or warm engine operation, idle control, acceleration, cruise, deceleration, transmission shifting, etc.Vehicle Speed: How fast the vehicle is going (MPH or KPH) affects transmission control, ignition timing, fuel metering, and several emission-control systems. It is also an input for other vehicle systems, such as cruise control, ABS, and traction control.Temperature: The temperature of the engine coolant, intake air, and transmission fluid affects fuel, ignition, and transmission control, as well as emission control.Pressure: Manifold pressure and barometric pressure are primary inputs for fuel and ignition control and transmission shifting. Most control systems use air pressure measurements as a starting point for the PCM to calculate engine loadSee page
156 Generic OBD II Software Standardized scan tool modes of operation are mandated.Generic OBD II Software requires selecting Generic or Global OBD II from the scan tool menu.See page 46
157 Generic OBD II Software Standardized OBDII modes allow ‘generic’ scan tools to access the same subset of information from all carsMode $01: Current parameter data (PIDs)Mode $02: Freeze Frame dataMode $03: ‘Confirmed’ emission-related DTCsDTCs that are (or recently were) commanding the MIL onMode $04: Clear DTCs and reset emission-related diagnostic informationMode $05: HO2S monitoring test resultsMode $06: Test results for non-continuously monitored systemsMode $07: ‘Pending’ emission-related DTCsMode $08: Bi-directional controls (never required/implemented for generic OBD)Mode $09: Vehicle data (VIN, Calibration ID, etc.)Mode $0A: ‘Permanent’ emission-related DTCsStored when MIL commanded onCannot be erased by scan toolOnly erased by OBD system itself once monitor runs and passesThe Generic OBD II Software must allow the technician to read and clear DTC’s and Freeze Frame data, read PID data, Monitor Status, and detailed Oxygen Sensor Monitor data. These are known as Modes $01 through Mode $05. Even though Modes $06 through Mode $0A (10) are defined by SAE J-1979, they are not available on all OBD II compliant scan tools (especially early versions of Generic OBD II software). However, many newer versions of Generic OBD II Software allow access to Modes $06 through Mode $0A.SAE requirements as of 2010.Permanent fault codes have nothing to do with how ‘severe’ a problem is. Any DTC that turns the MIL on gets stored both as a Mode $03 ‘confirmed’ DTC and a Mode $0A ‘permanent’ DTC. The differences include:Mode $0A DTC does NOT command the MIL onMode $0A DTC cannot be erased by any scan tool command or battery disconnectMode $0A DTC stays around until the MIL goes off and the OBD system runs that same monitor again and determines the system is passing.And Mode $0A is not Mode 10. don’t confuse hex with decimal because there is also a Mode $10 (non-generic). Leave it as Mode $0A if you really want to include the Modes—otherwise just use terminology like pending DTC, confirmed DTC, and permanent DTC.See page 47
158 OEM Enhanced OBD II Software Enhanced scan tools include additional diagnostic capabilities.These capabilities include non-standardized and non-emission related information not available in the Generic OBD II Software.Manufacturer specific DTCsManufacturer specific PIDsEnhanced “Snapshot” functionsBi-directional controlsSee page 47-48
159 OEM Enhanced OBD II Software It is advantageous to use both the Generic and Enhanced protocols.More dataBi-directional controlsIdentifying substituted values, etc.It is to your advantage to use both the Generic Software and the OEM Enhanced Software, or you may miss a lot of important diagnostic and repair data. Depending on the year, make, model, and/or engine, PID data, DTCs, Monitor Status, Freeze Frame, and other important data may or may not be available if you use only one type of software mode.See page
160 OEM Specific OBD II Software Manufacturer Specific Scan Tools/SoftwarePerforms OBD II related functions and interfaces with other vehicle computers.Most vehicles today has a multiplexed vehicle network system.Reprogramming functions.Increased number of PID and DTC data, descriptions, diagnostic tips, and strategies.Up-to-date technical support and upgrades directly from the vehicle manufacturer.The OEM Specific Software is only available from the Manufacturer, and is primarily used for specific vehicle diagnostic tests and data. This is because each and every vehicle manufacturer uses their own version of software inside the PCM. So for detailed access to the PCM software, such as bi-directional controls and reprogramming features, the OEM Specific Software may be the only way to use these certain features and functions.See page 48
161 OBD II 16-pin Connector Pin #1: Discretionary to Vehicle Manufacturers Pin #2: SAE J1850 Protocol “Hi Signal” [Data (+)]Pin #3: Discretionary to Vehicle ManufacturersPin #4: Chassis Ground (Typically B-)Pin #5: Sensor Ground (Typically B-)Pin #6: ISO CAN “Hi Signal” [Data (+)]Pin #7: ISO and Protocol “K-Line”Pin #8: Discretionary to Vehicle ManufacturersSee page 49
162 OBD II 16-pin Connector Pin #9: Discretionary to Vehicle Manufacturers Pin #10: SAE J1850 Protocol “Lo Signal” [Data (-)]Pin #11: Discretionary to Vehicle ManufacturersPin #12: Discretionary to Vehicle ManufacturersPin #13: Discretionary to Vehicle ManufacturersPin #14: ISO CAN “Lo Signal” [Data (-)]Pin #15: ISO and Protocol “L-Line”Pin #16: Unswitched B+See page 49
163 ASE L1 Composite Vehicle scan tool Data In this example there are 63 PIDs listed with Min/Max values for each data parameter listedRefer students to page 13 of the ASE type 3 composite vehicle handoutRemember that to properly diagnose a vehicle the technician has to find out the operating parameters of the specific vehicle they are working onPID = Parameter Identification Data is data displayed by a scan tool on the PCM/ ECM inputs and outputs.See page 51
165 Monitors Monitors are self tests of emission components or systems. Comprehensive ComponentMisfireFuel TrimEGRO2 SensorO2 HeaterCatalytic ConverterEVAPAir Injection SystemsRefer to page 12 of the composite vehicle titled “Drive Cycle”.Enable criteria- Set of conditions that must be met before a monitor can run.See page 53
166 MonitorsThree or more incomplete monitors will cause a vehicle to fail smog inspection for 1996 to 2000 model year vehicles and 2 or more on 2001 and newer vehicles.Monitors are designed to run to completion during normal vehicle operation.Enabling criteria must be met for monitors to run.Enabling criteria for each monitor is different.Drive cycle would include enabling criteria for all monitors to run.This is a generic list of monitors remember to refer to manufacture specs for the specific vehicle that is being worked on. Refer to page 55 of the Reference Manual.Refer to ET Blast # 29604
167 Mode $06 DataMode $06 displays test results for non-continuous monitors.Mode $06 can give the results of a two trip monitor in one trip.Can confirm a successful repair after one trip.Test results can indicate if a monitored system is close to failing.Mode $06 was one of the original criteria’s that vehicle manufacturers were required to include in their on-board computer systems (OBDII).See page 59
168 Terms Used in Mode $06 Data TID = Test Identification – The system being tested (MIDs = Monitor Identification in CAN systems)CID = Component Identification – The component of the system being tested.TLT = Test Limit – To pass a test, a test value must be either a minimum or maximum value ( or between a min/max value)Hexadecimal ($) = Numeric/Alpha unit that indicates a specific TID/CID or test value (Example: $02)Raw Data = Numeric data indicating the actual test results.Manufacturer’s Conversion Factor = Used to convert test data to values that can be used to diagnose a system (volts, Ohms, amps, inches of mercury, etc.).Test Value = Actual test results.Results = Indicates whether system/component either passed or failed a test.Limit Type = Test pass/fail limitsSee page 61
169 Mode $06 Data**Non-Cont. Monitoring Test Result**ECU ID: $10 Test ID: $02 Component: $02Min: Max: Value:Results: FailThis scan tool shows the actual test results of the monitorNote the minimum and maximum parametersSee page 59
170 Mode $06 DataA vehicle failed for a P0420 (CAT efficiency below threshold)A new CAT was installed and codes cleared.Check the enabling criteria to run the CAT monitor and run that drive cycle.See page 61
171 Vehicle failures due to monitors not run to completion
172 Mode $06 Data Vehicle fails an ASM test for monitors not run. Smog technician advises vehicle owner to drive the vehicle for 50 miles.Vehicle owner returns two days later with the same results of monitors not running.A diagnosis has been authorized.Diagnosis has been made and no problems found. Vehicle now referred to Referee.See page 63
173 Mode $06 DataSee page 63Mode $06 shows TID $02 CID $60 has failed. (EVAP weak vacuum test 1)Possible reason EVAP Monitor has not run
174 Mode $06 DataSee page 63TID $07 CID $4D shows EGR passed at maximum
175 Mode $06 Data Code P0404 found in pending (Control Circuit) See page 63Code P0404 found in pending (Control Circuit)
176 Mode $06 Data Vehicle is at Operating temperature See page 63Vehicle is at Operating temperatureNote ECT input is low at 111 degreesNote fuel trims at negative -32.8
177 Mode $06 Data Testing the EGR circuit See page 63Testing the EGR circuitFound a voltage drop of 1.57 volts on the ground sideCause of pending code P0404
178 Mode $06 Data Testing the ECT circuit See page 63Testing the ECT circuitFound 2.24 voltage drop on the ground side causing a higher voltage signal to PCM.ECT sensor itself is within manufacture specs.Causing Injector pulse width to increase.
179 Mode $06 DataThe ECT and EGR harnesses have been repaired, and the codes and monitors reset. A drive cycle has been completed and all the monitors have run to completion. Vehicle now passes a smog check and vehicle owner feedback states vehicle is getting better fuel economy.See page 63
180 2011 BAR Update Course Catalytic Converter Testing
181 Objectives The purpose of the catalytic converter The fundamental needs for proper catalytic converter operationCatalytic converter replacement requirements – CARB Installer’s ListCauses of catalytic converter failuresPre-OBDII catalytic converter testingOBDII catalytic converter testing
182 The CatalystCatalysts are needed to reduce emissions to acceptable levels without dramatically reducing performance and fuel economy. This is true of HC, CO and NOx, but NOx is the emission that is most dependent on the catalyst for emissions complianceThere are two types of catalysts:Reduction catalysts cause NOx to be reduced into O2 and N2.Oxidation catalysts cause HC and CO to oxidize with any available oxygen into CO2 + H2O.*Unfortunately, oxidation will only occur when there is enough free oxygen, and reduction is very hard to achieve with the high oxygen levels that occur in lean burn operation.
183 The CatalystA catalyst can not clean up CO and HC unless there is enough oxygen in the exhaust.Many catalysts can not clean up NOx unless the level of oxygen in the exhaust is very low.There is no fuel mixture that allows CO, HC and NOx to all be catalyzed at maximum efficiency.Gasoline Direct Injection (GDI) engines and Homogeneous Charge Compression Ignition (HCCI) engines operate under lean burn conditions frequently. Hybrid electric vehicles often operate their internal combustion engines for shorter periods of time that would prevent traditional catalytic converters from reaching operational temperatures.
184 The CatalystMany late model cars depend heavily on the catalyst to reduce NOx at extremely high levels (95+%). This simply is not possible unless the oxygen level is low enough. If carbon deposits or other problems increase the exhaust oxygen level, a perfectly good catalyst will operate at reduced efficiency.Some late model cars depend on the catalyst to clean up over 99.3% of their NOx emissions.This will only occur if the exhaust oxygen level is very low.Many minor problems can increase exhaust oxygen levels and inhibit catalyst efficiency.
185 Catalyst Approval Criteria As of January 1, 2009, CARB approval/exemption requirements for all aftermarket replacement catalytic converters changed.These changes increased performance requirements and improved identification labels. As a result, aftermarket converters now come closer to the original equipment converters in both performance and longevity.
186 Catalytic Converter Replacement Technicians and vehicle owners do NOT have the option of replacing original equipment catalytic converters without first meeting the requirements of the CARB Installers Checklist for New Aftermarket Catalytic Converters, as applicable-The vehicle model is specifically included in the application list for the catalytic converter model I intend to install, and the converter model is approved for use in California.I have verified that the vehicle manufacturer’s warranty for the stock catalytic converter has expired. Warranties will range from a minimum 7 years/70,000 miles to 15 years/150,000 miles.I have confirmed the need for a replacement catalytic converter. If the stock converter is still installed, a diagnosis that it is malfunctioning is required.
187 Catalytic Converter Replacement The replacement converter will be installed in the same location as the stock converter (the front face location will be within three inches compared to the stock design).All oxygen sensors will remain installed in their stock location(s).The catalytic converter will be installed on a “one for one basis (only one OEM converter is being replaced by the converter to be installed). Decreasing or increasing the number of catalytic converters (compared to the stock configuration) is prohibited.Warranty Card- I have:Filled out the warranty cardObtained the customer’s signature an the cardAttached the card to the original repair orderReturned a copy of the warranty card to the catalytic converter manufacturerI have filed and will maintain a copy of all documentation for a period of at least four years from the date of installation.
188 Catalytic Converter Replacement Installers shall keep documentation regarding the installation of the new catalytic converter including all of the above information. This documentation shall be made available to CARB or it’s representative as provided for in title 13, section 222(b)(8). All such records shall be maintained for four years from the date of sale of the catalytic converter.
189 What Can Damage A New Catalyst? Quality catalytic converters can perform well for hundreds of thousands of milesAnything that significantly increases the amount of HC and/or CO that is oxidized in the converter will increase the operating temperature of the catalystFailing to use manufacturer approved engine oilCoolant seeping into the combustion chamber or exhaust
190 What Can Damage A New Catalyst? If any of the following conditions exist, the customer (or referring shop) should be notified that the engine might have existing faults that could damage the new converter:CO in excess of 2.0% (pre-catalyst)HC in excess of 400 ppm (pre-catalyst)Indications of high oil consumptionIndications of combustion/coolant leaksIndications of O2 sensor faultsIndications of modifications or poor maintenance
192 Catalytic Converter Cranking Test There is typically no CO2 present in the atmosphere. CO2 is a product of combustion. Therefore any carbon dioxide emissions measured during typical starter draw test, with ignition disabled must be created in the catalytic converter.A good catalytic converter should be capable of converting the Hydrocarbon fuel (HC) that is pumped through the engine during the starter test to 13% carbon dioxide.In order to create 13% CO2 during a starter draw test the following must occur:The catalytic converter must be completely warmed up.Fuel delivery must be functioning normally. *The CO2 is being created by converting the fuel that is being pumped through the engine.Ignition must be completely disabled.
193 Catalytic Converter Cranking Test THE TEST:1. Start the engine and drive the car to insure that it is warmed up completely.2. Run the engine at 2000 rpm to insure that the catalytic converter is hot.3. Turn off the ignition or hit the analyzer kill switch.4. IMMEDIATELY after the engine stops, disable the ignition (ground the coil secondary or disconnect the coil primary) and crank the engine over while watching the CO2 levels on the exhaust analyzer.NOTE: The fuel system must remain functional! Do not disable rpm sensor or engage clear flood mode! Disable the ignition system only! Do not allow the converter to cool down!
194 Catalytic Converter Cranking Test 5. The CO2 level should reach and maintain 13% in about 10 seconds. If the CO2 level does not reach at least 13%, or the CO2 level only spikes to 13%, the catalytic converter is weak.If the CO2 level is below 13% make sure that there is sufficient HC and O2 to make the CO2 from. If the CO2 level drops below 1% or HC drops below 500 ppm the test will not be valid.*This test is difficult to perform on many DIS cars since the ignition is not easily disabled.Use the snap throttle test on such cars.
196 Catalytic Converter Snap Throttle Test When the engine is running at a stoichiometric 14.7:1 fuel mixture with no air injection there is very little oxygen in the exhaust. Cars equipped with carburetors will have higher normal levels of oxygen due to poorer fuel atomization and vaporization.During a snap throttle test, CO will increase due to a suddenly rich mixture on acceleration. CO will continue to increase until the O2 level begins to rise. During this snap acceleration all excess oxygen will be used up by the catalytic converter to convert CO to CO2. As the O2 level rises O2 will be used up by the catalytic converter to convert CO to CO2 and the CO level will begin to drop as O2 rises. A good catalytic converter will therefore prevent the O2 level from exceeding 1.2% until the CO level begins to drop.
197 Catalytic Converter Snap Throttle Test THE TEST:1. Drive the car until the engine and catalytic converter are fully warmed up.2. Disable the air injection system.3. Run the engine at 2000 rpm and wait for stable exhaust readings with O2 level no higher than 0.5%. Propane enrichment may be used to reduce O2 level to 0.5%.4. Snap and release the throttle.5. Watch the CO emissions climb and note the oxygen level at the instant the CO level peaks. Oxygen level at the instant that CO level peaks should not exceed 1.2%.
198 Catalytic Converter Snap Throttle Test THE TEST:Note: It is normal for Oxygen level to rise after CO has peaked.If the O2 level exceeds 1.2% before the CO level peaks the catalytic converter is weak.This test works best on cars that have sequential fuel injection and DIS. The cranking catalytic converter test tends to be difficult to perform on these same cars.
200 Catalytic Converter Invasive Test Catalytic converter efficiency can be determined by sampling the exhaust gas before and after the catalytic converter. Kits are available from Thexton (No. 389), OTC and others to tap through single wall exhaust pipes. Other pre-CAT sampling locations may include the EGR port, EGO port and air injection ports. (EGO is not recommended). Record both the before cat and tailpipe exhaust gas with the engine well tuned, preconditioned, no exhaust leaks and no air injection. Fuel mixture may have to be manipulated and/or misfires induced to create the proper oxygen level for proper evaluation.
201 Catalytic Converter Invasive Test (HC in) - (HC out)x 100 = CAT HC efficiency(HC in)HC oxidation efficiency should be 90% when O2 in exceeds 1% and O2 out exceeds 0.5% You may need to induce a misfire to create the proper O2 levels.(CO in) - (CO out)x 100 = CAT CO efficiency(CO in)CO oxidation efficiency should be 90% when O2 in exceeds 1% and O2 out exceeds 0.5%
202 Catalytic Converter Invasive Test (NOx in) - (NOx out)x 100 = CAT NOx efficiency(NOx in)NOx reduction efficiency should be 90% when O2 in is less than 0.5%. This test may require loaded mode testing and/or disabling EGR. It may also be necessary to artificially enrich the air-fuel mixture to reduce O2 content below 0.5%.
203 Catalytic Converter Invasive Test NOTE: EPA certifications only require catalysts to oxidize CO & HC at 70% efficiency, and to reduce NOx at 60% efficiency. This may not be sufficient to allow some cars to pass ASM tests. Some cars may require 90% efficiency in NOx reduction. Others may be fine with less than 50%.The oxidation and reduction efficiency of good catalysts vary due to oxygen levels in the exhaust system during normal running conditions of those cars. 2-way catalysts operating with high oxygen levels in the feed-gas should meet the above standards for CO and HC oxidation. All 3-way catalysts operating with low oxygen levels in the feed-gas should meet the above standards for CO & HC oxidation and NOx reduction.
205 Catalytic Converter Light Off Test This test must be performed with the engine cold.Start the cold engine and monitor exhaust gas at 2500 rpm during warm up.Exhaust emission readings should be relatively stable except during the following three events:1. Initial start up & stabilization.2. Initialization of closed loop.3. Catalytic converter “light-off”.This can be graphed or “traced” so that the readings before and after converter light off can be compared. Use the same formula shown in the “Invasive Test”.
207 Catalytic Converter Misfire Test When a misfire occurs the catalytic converter releases a tremendous amount of heat as it oxidizes the unburned HC into H2O and CO2. The increased temperature that this causes increases the Catalyst efficiency. This reaction allows us to test the catalyst by inducing a misfire.THE TEST:1. Allow the car to run for several minutes at 2500 rpm after it is properly warmed up.2. Disable one spark plug. Do NOT allow the engine or exhaust system to cool down as you do this. It is permissible to turn the engine off while disabling the spark plug, but this must be done and the engine restarted within three minutes. Some engine analyzers will allow you to kill an individual cylinder without turning the engine off.
208 Catalytic Converter Misfire Test 3. As you induce the misfire, the HC will increase dramatically for several seconds. Then, as the catalyst heats up, the HC level should drop off significantly. Record the Peak HC level and the level that HC drops to as it gets hot.A good catalytic converter will be able to reduce the HC emissions to about 50% or less of the peak HC emissions in just a few seconds.This test must be performed with caution. Do NOT perform this test for extended periods or under a load. A catalytic converter can overheat to the point of melt-down in as little as 12 seconds if multiple spark plugs are disabled while under load. Do not disable multiple cylinders and do not perform the test under loaded conditions.
210 Catalytic Converter Temperature and 4-Gas Test Completely warm up the engine and exhaust system. Run the following test using a 4 or 5 gas analyzer and an infrared temperature sensing gun.The accuracy of infrared temperature sensing varies according to the "emissivity" of the surface being sensed. Sometimes it is helpful to paint the surfaces with a quick drying flat black paint before testing. Painting is recommended if the two surfaces have different surface finishes.
211 Although this is the least desirable test, the CAP program will accept this test as second of the two required tests before condemning a catalytic converter.
214 OBDII Catalytic Converter A properly operating catalytic converter uses oxygen to oxidize HC and CO into CO2 and O2. The process changes the oxygen level in the exhaust. Under tightly controlled conditions, the PCM will initiate a pattern of fuel control commands and monitor the oxygen sensor response. In order to pass the monitor test the oxygen sensor response must fall within a pre-determined pattern. The pattern is different for each car but the rear oxygen sensor is often compared to the front oxygen sensor to identify changes that the catalytic converter causes in exhaust oxygen content.
215 Catalytic Converter OBDII Monitor The OBDII monitor test is typically run automatically on every trip in which the required enable criteria are met. The enable criteria are different on each vehicle. Details of the enable criteria and the drive cycle required to meet those criteria can be found in published service manuals.As mentioned elsewhere in this document, many vehicles that use “exponentially weighted moving averages” as part of the OBDII catalyst monitoring have reduced accuracy immediately after the memory has been cleared. Under these temporary conditions, false fails and false passes are more likely to occur. With this possible exception, OBDII monitors are very accurate. If in doubt, clear codes and retest.
216 OBDII Catalytic Converter Test Check List Confirmation of baseline gas dataConfirmation of proper engine mechanical operationConfirmation of proper ignition system operationConfirmation of proper fuel system operationCheck for Closed Loop Fuel Control
217 OBDII Catalytic Converter Test Check List Check data stream for fuel trimCheck readiness monitorsCheck for pending codesCheck for unrelated codesCheck Exhaust system for leaksVisualAudiblePressure TestSmoke Test the Exhaust System for LeaksInstructor should discuss Lambda/Lambda calculator.
218 OBDII Catalytic Converter Test Check List Secondary Oxygen Sensor TestingActivityGraphing MeterVolt MeterScan ToolLocating SpecificationsManufacturer DocumentationOther service information providersRelated fault code flow chartsMode 6 data parameters
219 Scenario #1 On an OBDII equipped vehicle All test results are ok to this point, but NOx is still too highWhat test(s) should be performed?Invasive Test with calculationsWhat is the expected Oxygen Sensor results? Why?This scenario is an example. Instructor can add additional scenarios as necessary.Light-Off Test with calculationsWhat is the expected Oxygen Sensor results? Why?
221 Instructors should use this time to expand on any components of Catalytic Converters and Testing. Consider scenarios or hands on training
222 BAR wishes to thank the following individuals for their contributions THANK YOUBAR wishes to thank the following individuals for their contributionsNorthern Group,Catalytic Converter TestingChristine VinsonDennis ShortinoJustin BunchKevin McCartneyKurt ShadboltLarry WilliamsMichael SherburneRay OrtizSouthern Group,OBD IIJay HartleyJonathan SummersJose VallejoMark EllisonMichael GaribaySteven Tomory