© A.T.T.S. Inc I/M Solutions 2012 Diesel Training What Works? What Doesn't? Jerry “G” Truglia

© A.T.T.S. Inc Diesel Training Gas engine technicians say, “We don’t work on diesels!” Why? There is not much of a difference between a gas and a diesel engine. Culturally, technicians hate diesels. Remember those early GM and VW diesel engines? Well, the diesel engine of today is very reliable and has been utilized in Europe and North America without many problems.

© A.T.T.S. Inc Suck, Squeeze, Bang, and Blow The more efficient an engine is, the better. A gas engine is about 25 to 28 percent efficient while the diesel engine is about 35 to 40 percent efficient. Both engines covert fuel into energy through four cycles: suck, squeeze, bang, and blow.

© A.T.T.S. Inc The Difference Between Gasoline and Diesel Engines Unlike the gas engine, there are no spark plugs and fuel does not go in on the intake stroke.

© A.T.T.S. Inc The Difference Between Gasoline and Diesel Engines

© A.T.T.S. Inc The Difference Between Gasoline and Diesel Engines

© A.T.T.S. Inc The Difference Between Gasoline and Diesel Engines

© A.T.T.S. Inc So, What’s the Difference? In a gasoline engine fuel is introduced with air that is then compressed by pistons and ignited by a spark plug to produce combustion. In a diesel engine the incoming air is compressed first creating enough heat to ignite the incoming injected fuel. The diesel system does not require spark to make the fuel hot enough to ignite. Instead, it uses purely the compression of air. In very cold weather, glow plugs or intake heaters might be used to make the air warmer, but they are generally used only at start up and do not create any sparks.

© A.T.T.S. Inc So, What’s the Difference? The main differences between the gasoline engine and the diesel engine are the following: A gasoline engine compresses at a ratio of 8:1 to 12:1, while… A diesel engine compresses at a ratio of 14:1 to as high as 25:1.

© A.T.T.S. Inc Emission Controls

© A.T.T.S. Inc Exhaust Gas Recirculation Valve (EGR) The Exhaust Gas Recirculation (EGR) valve controls the amount of exhaust that is recirculated back to the intake manifold. 6.0L EGR and Cooler

© A.T.T.S. Inc Diesel Oxidation Catalyst (DOC) The first component in the system that helps reduce exhaust emissions is the Diesel Oxidation Catalyst (DOC). The job of the DOC is to reduce HC, CO and some particulate matter. The particulate matter cannot be reduced enough to meet emission so a Diesel Particulate Filter (DPF) has to be added.

© A.T.T.S. Inc Diesel Particulate Filter (DPF) Exhaust gases flow through the DPF prior to flowing into the muffler and out the tail pipe. The job of the DPF Diesel particulate filters drastically decrease the amount of diesel particulates (soot) and unburned hydrocarbons released from the combustion of diesel fuel. The honeycomb structure of the DPF captures soot as it passes through the filter. Most DPFs reduces diesel particulate matter emissions by approximately 90 percent. The problem associated with DPF's is that over time, soot collecting in the DPF can clog it, resulting in decreased performance and fuel efficiency.

© A.T.T.S. Inc DPF Regeneration-Types of Regeneration There are two types of Regen, Passive and Active. Passive Regen occurs during normal vehicle operation when the conditions are right, similar to OBD II monitors’ enabling criteria. Engine load conditions have to produce enough load and exhaust temperature in order for Regen to occur. This process is not noticed since it is done without driver input or the ECM commanding anything special. This Regen may occur during high speeds or under an engine load. Courtesy of Cummings

© A.T.T.S. Inc Types of Regeneration Active Regen occurs when it is commanded by the ECM. If the ECM detects that the DPF has excessive backpressure, regen will be commanded. This action is usually not noticed in most cases by the driver if the vehicle is driven 30 mph or above for at least 20 to 30 minutes. If the active regen process is interrupted for any reason it will continue where it left off on the next drive cycle that meets the same criteria. If the vehicle does not meet the criteria, a light will be illuminated to warn the drive that a regen has to be done. Courtesy of Cummings

© A.T.T.S. Inc Stages of Regen Some instrument panel may have five panel lamps to monitor engine and exhaust after-treatment status. Remember that the Check Engine lamp and Stop Engine lamp refer to basic engine functions only. The three other lamps are the Diesel Particuate Filter (DPF) lamp, the High Exhaust System Temperature (HEST) lamp, and the Malfunction Indicator Lamp (MIL) lamp. The amber Check Engine warning lamp indicates a fault with the engine controls has occurred. The operator can drive the vehicle to the end of their shift and have it repaired as soon as possible.

© A.T.T.S. Inc Stages of Regen The red Stop Engine warning lamp indicates a major engine fault that may result in engine damage has occurred. The operator should move the vehicle to a safe location and shutdown the engine. The Diesel Particulate Filter (DPF) will illuminate when a regeneration is necessary. There are progressive stages that are needed for regeneration indicated by this lamp as described below. A solid lamp indicates regeneration should take place within a reasonable amount of time. A flashing lamp indicates that the filter has become loaded to a point where a regeneration is required immediately.

© A.T.T.S. Inc Stages of Regen The first stage (solid) should allow the vehicle to complete a typical shift of operation depending on vehicle duty cycle. This provides time for a vehicle to return to a repair facility or change duty cycle (increase exhaust temperatures by normal truck use) without impacting the current drive. In the event the DPF light has recently activated, the vehicle can be driven onto a highway or put into pump mode to put load on the engine allowing an automatic regeneration to clean the DPF.

© A.T.T.S. Inc Stages of Regen The second stage (flashing) requires the operator to initiate a regeneration immediately to clean the DPF. This can be accomplished through either automatic regeneration (driving or pumping/adding fuel to the DPF) or a parked regeneration. The DPF lamp will turn off during the parked regeneration event. The third stage (DPF flashing and Check Engine lamp illuminated) indicates that an automatic regeneration will no longer be allowed. The vehicle should be moved to a safe location where a parked regeneration can be immediately initiated.

© A.T.T.S. Inc Stages of Regen The fourth stage (DPF flashing, Check Engine lamp illuminated and Stop Engine lamp illuminated) indicates that damage to the after-treatment device is eminent and a parked regeneration should be performed immediately. The High Exhaust System Temperature (HEST) lamp provides an indication to the vehicle operator that an active regeneration has been initiated and that the exhaust system temperature is elevated beyond the temperature threshold. This lamp does not indicate a failure of any type, it merely indicates elevated operating temperatures. The HEST lamp will not illuminate if road speed exceeds 5 mph.

© A.T.T.S. Inc Stages of Regen The Malfunction Indicator (MIL) Lamp provides an indication to the vehicle operator that a fault has occurred on an emission related component. This lamp may illuminate at the same time as the Check Engine lamp. The operator can drive the vehicle to the end of their shift and call service to remedy the problem.

© A.T.T.S. Inc Diesel Exhaust Fluid (DEF) and Selective Catalytic Reduction (SCR) Starting in 2010 the EPA mandated another emissions reduction, this time in NOx. The manufacturers came up with another way to reduce NOx by using SCR. The SCR system uses a liquid called DEF that is stored in a separate tank and is injected into the exhaust stream ahead of the SCR catalyst. This fluid is used in the diesel exhaust to convert NOx emissions into nitrogen and water vapor, two things that are not harmful to us or the environment.

© A.T.T.S. Inc Diesel Exhaust Fluid (DEF) and Selective Catalytic Reduction (SCR)

© A.T.T.S. Inc Emissions Reduction Options Exhaust Aftertreatment Level I: Diesel Oxidation Catalyst (DOC) – A DOC is an exhaust after-treatment device that employs a catalyst to break down pollutants in the exhaust stream into less harmful components.

© A.T.T.S. Inc Emissions Reduction Options Exhaust Aftertreatment Level II: Flow-Through-Filter (FTF) – An FTF is an exhaust after-treatment device designed to combine high filtration efficiency with low maintenance.

© A.T.T.S. Inc Emissions Reduction Options Exhaust Aftertreatment Level III: Diesel Particulate Filter (DPF) – A DPF is an exhaust after-treatment device that uses wall-flow technology to prevent PM in the exhaust stream from being released to the atmosphere. Particles are trapped in the filter and then oxidized by high temperatures and/or a catalytic coating on the filter. Many DOC are packaged together with the DPF.

© A.T.T.S. Inc OBD II For Heavy Duty Engines (HD OBD II) The EPA has ruled that 2010 and subsequent model year Heavy Duty Engines (HD OBD) are required to have the same OBD II that gasoline vehicles have, including Monitor checks.

© A.T.T.S. Inc OBD II For Heavy Duty Engines (HD OBD II) The Monitors for the OBD II Diesel system are: 1. Fuel System 2. Misfire 3. EGR 4. Boost Pressure 5. Non Methane Hydrocarbon (NMHC) 6. Oxides of Nitrogen (NOx) Converting Catalyst 7. NOx Absorber 8. Particulate Matter (PM) Filter 9. Exhaust Gas Sensor 10. Variable Valve Timing (VVT) Control System

© A.T.T.S. Inc Training Through The Internet Webcasts provide just in time training along with YouTube Review Saving time and money by using interactive training Preps technicians on important updated information

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