1. Contents
Click a Section Tab

2. Engine Overall
Valve Mechanism
Lubrication System
Cooling System
Intake and Exhaust System
Fuel System
PCV
Engine Control System

3. Engine Overall 3UR-FE Engine-W -Q -V -C -A
3UR-FE Engine
V8 (90-degree), 5.7-liter, 32-valve, DOHC engine with Dual VVT-i, ETCS-i, ACIS and AI system
[Engine feature]
V type 90-degree, 8 cylinders, 5.7-liter, 32-valve, DOHC gasoline engine
Equipment:
- Dual hydraulic VVT-i (Variable Valve Timing-intelligent)
- ETCS-i (Electronic Throttle Control System-intelligent)
- ACIS (Acoustic Control Induction System)
- AI (Air Injection) System

4. Engine Overall Features -W -Q -V -C -A MRE Type VVT Sensor
Delivery Pipe with Pulsation Damper Function
Separator Case for PCV
Hydraulic Lash Adjuster
Vacuum Actuator Type ACIS
Dual VVT-i
4 Timing Chains
[Features]
- Spiny liner
- Water jacket spacer
- Dual VVT-i (hydraulic type for intake and exhaust)
- Hydraulic lash adjuster
- 4 timing chains
- Engine Coolant Distribution Pathway
- Element replacing type oil filter
- Vacuum actuator type ACIS
- Delivery pipe with pulsation damper function
- Separator case for PCV
- Long reach type spark plug
- 4 flat type knock sensors
- MRE type VVT sensor
4 Flat Type
Knock Sensors
Engine Coolant
Distribution Pathway
Water Jacket Spacer
Long-reach
Type Spark Plug
Element Replacement Type Oil Filter
Spiny Liner

5. 32-Valve DOHC Chain Drive,
Engine Overall -W -Q -V -C -A
Specifications
Model
LX570
LS460L / LS460
Engine
3UR-FE
1UR-FSE
1UR-FE
No. of Cylinders and Arrangement
8-cylinder,
V type 
Valve Mechanism
32-Valve DOHC Chain Drive,
Dual VVT-i
32-Valve DOHC,
Chain Drive,
(VVT-iE for Intake)
Combustion Chamber
Pentroof Type
Displacement
cm3 (cu. in.)
5663
(345.6)
4608
(281.2)
Bore x stroke
mm (in.)
94.0 x 102.0
(3.70 x 4.02)
94.0 x 83.0
(3.70 x 3.27)
Max. Output
rpm
rpm) -A
5600
5600)
6400
6400) -
Other
5600
6400
6400
Max. Torque
rpm
rpm)
3600
3600)
4100
( 4100)
3200
4100
4000

6. Engine Overall Specifications -W -Q -V -C -A Model LX570
LS460L / LS460
Engine
3UR-FE
1UR-FSE
1UR-FE
Compression Ratio
10.2 : 1
11.8 : 1
10.8 : 1
Firing Order 
Valve Timing
(°)
Cylinder No.
All Cylinder
#4,5,7,8
#1,2,3,6
Intake
Open
(BTDC)
-2 – 58
-14 – 26
-10 – 30
Close
(ABDC)
82 – 42
78 – 38
Exhaust
(BBDC)
60 – 25
64 – 29
60 – 28
64 – 32
(ATDC)
0 - 30
4 – 39
0 – 35
4 – 36
0 – 32
Emission Regulation NA
LEVII ULEV -
Europe
EURO IV
Except Europe
EURO IV, EURO III or EURO II*
EURO III
or EURO II*
*: It is different depending on the countries

7. Engine Overall Major Difference From 1UR-FSE / 1UR-FE on LS460 -W -Q
Model
LX570
LS460L / LS460
Engine
3UR-FE
1UR-FSE / 1UR-FE
Cylinder Head Cover
Aluminum
Magnesium
Crankshaft Pulley
Without balance piece
With balance piece
Camshaft
Conventional Type
Composite Camshaft
VVT-i
Dual VVT-i
(IN & EX: Hydraulic)
(IN: VVT-iE / EX: Hydraulic)
Fuel System
Port Injection
D-4S (Direct and Port) [-FSE]
Return Type
Return-less Type
Pressure regulator is installed at delivery pipe
Pressure regulator is installed at fuel pump
Fuel Pump Control
(In tank pump)
Fuel Pump ECU
(3-step)
Resister
(2-step)
Spark Plug
Single Ground Electrode
Triple Ground Electrode [-FSE]
Single Ground Electrode [-FE]
Air Flow Meter
1 air flow meter
2 air flow meters
ACIS
Operated by vacuum actuator
Operated by DC motor
Air Injection System
With (2-pump type)
N.A.
Cooling Fan
Fan coupling
PWM controlled electric fan
ECM
Dash panel penetration installation
In the ECU box

8. Valve Mechanism Timing Chain
Same as 1UR-FSE / -FE -W -Q -V -C -A
Timing Chain
To ensure highly accurate valve timing, separate primary timing chains are used
Primary Chain (RH)
Secondary Chain (LH)
Chain Tensioner
(for Secondary)
Secondary Chain (RH)
Chain Tensioners
(for Primary)
4 timing chains are used.
To ensure highly accurate valve timing, separate primary timing chains are used.
4 chain tensioners are used for each chain.
Chain Tensioner
(for Secondary)
Primary Chain (LH)

9. Hydraulic VVT-i for Intake Hydraulic VVT-i for Exhaust
Valve Mechanism -W -Q -V -C -A
Dual VVT-i
Hydraulic type VVT-i is used for intake and exhaust valve
Hydraulic VVT-i for Intake
VVT-i is used for intake and exhaust valve (Dual VVT-i).
Hydraulic VVT-i (3-vane) is used for intake valve.
Hydraulic VVT-i (4-vane) is used for exhaust valve.
Hydraulic VVT-i for Exhaust

10. Laminated Type Oil Cooler
Lubrication System -Q -V -A
Oil Cooler
Laminated aluminum core oil cooler is used for compact, lightweight and high radiation performance
: Oil Flow
: Coolant Flow
Oil Filter Bracket
Spacer
Oil cooler is equipped only for –A (with towing package), –Q and –V as standard equipment.
Laminated aluminum core oil cooler is used for compact, lightweight and high radiation performance.
Laminated Type Oil Cooler
Oil Filter Cap

11. Engine Coolant Distribution Pathway
Cooling System
Same as 1UR-FSE / -FE -W -Q -V -C -A
Engine Coolant Distribution Pathway
Cylinder head and cylinder block is cooled by coolant from the engine coolant distribution pathway
Engine Coolant Distribution Pathway
Engine coolant distribution pathway distributes the coolant to the cylinder head and the cylinder block.
Coolant to the cylinder block is distributed equally to each cylinder.

12. Intake and Exhaust System-W -Q -V -C -A
Exhaust Manifold
Air injection pipe is provided for the air injection system
Air Injection Pipe
Exhaust manifold and air injection pipe is 1 piece.
Exhaust manifold with TWC for except –A.
TWC
Exhaust Manifold RH
(For -A)
Exhaust Manifold RH
(For Except -A)

13. Intake and Exhaust System-W -Q -V -C -A
Main Muffler
2-way exhaust control system is used to decrease the back pressure
Control Valve
[Engine Low Speed (Valve Closed)]
Since the pressure in the main muffler is low, the control valve is closed. Hence exhaust gas does not pass the bypass passage, and exhaust noise is decreased in the main muffler.
[Engine High Speed (Valve Opened)]
The valve opens as the engine speed and the back pressure in the muffler increase.
This allows a large volume of exhaust gas to pass the bypass passage, thereby substantially decreasing the back pressure.
Low Engine Speed
(Valve Closed)
High Engine Speed
(Valve Opened)
Reduce noise
Decrease back pressure

14. Pulsation damper function
Fuel System
Same as 1UR-FSE / -FE -W -Q -V -C -A
Delivery Pipe
Pulsation damper function is integrated in the delivery pipe
Pulsation damper function
Delivery Pipe
Inner Pipe
Pulsation damper function is integrated in the delivery pipe. Conventional pulsation damper is discontinued.
The inner tube is deformed by fuel pressure and absorbs the fuel pulsation.
Fuel

15. Fuel System
Same as 1UR-FSE / -FE -W -Q -V -C -A
Injector
The injector wire harnesses are combined into a single connector at each bank for improved serviceability
Injector Wire Harness
(RH Bank)
Injector Wire Harness
(LH Bank)

16. Fuel Tank Solenoid Return Valve
Fuel System -Q -V -C
Fuel Tank (Dual Fuel Tank Model Only)
Jet pump is used for the fuel transfer from sub tank to main tank
Fuel Inlet
One-way Valve
Fuel Inlet
Engine
Engine
Fuel Tank Solenoid Return Valve
Sub fuel tank is standard equipment for –Q, -V and –C.
[Material of the fuel tank for all model]
Main Tank: Plastic made (multi-layer)
Sub Tank: Steel made
Fuel Pump
Main Tank
(93-liter)
Sub Tank
(45-liter)
Main Tank
(96-liter)
Sub Tank
(45-liter)
Jet Pump
Fuel Pump
LX570
LX470

17. Oil Separator Mechanism
PCV
Same as 1UR-FSE / -FE -W -Q -V -C -A
Separator Case
Oil separator mechanism is included to the separator case and cylinder head cover becomes compact
: Blowby Gas
: Fresh Air
Oil Separator Mechanism
Oil
Mist
Blowby Gas
PCV Valve
Separator Case
Cylinder head cover becomes compact by integrating the oil separator mechanism in the separator case.

18. Engine Control System Knock Sensor
Same as 1UR -FSE / -FE -W -Q -V -C -A
Knock Sensor
4 knock sensors are installed inside the V-bank
knock Sensor
Front
4 knock sensors are used to ensure the reliability of knock detection performance.

19. Air Injection Control Valves
Engine Control System -W -Q -V -C -A
Air Injection System
The air injection system to quicken the warming-up the TWC during the cold start-up
Air Injection Control Valves
Air Filters
Electric Air Pumps
2-pump type air injection system is used to improve exhaust emission.
The system to quicken the warming-up the TWC during the cold start-up.
This system is equipped for all models.
[Operation Conditions]
After cold engine start
- THW is 5 to 45 °C (41 to 113 °F)
- THA is 5 °C (41 °F) or more
[Operating Time]
Approx. 60 – 80 seconds
AI system operates until the accumulated intake air volume exceeds the predetermined value.
Note: The ECM estimates the amount of air to the TWC based on the signals from the air flow meter.
TWC

20. Engine Control System Air Injection System System Diagram For Bank 1-W -Q -V -C -A
Air Injection System
System Diagram
Engine Coolant Temperature Sensor
Mass Air Flow Meter
Intake Air Temperature Sensor
ECM
Air Injection
Control Driver
Electric Air Pump
Air Pressure Sensor
Air Injection
Control Driver
Air Pressure Sensor
Air Switching Valve
Air Switching Valve
Electric Air Pump
For Bank 1
For Bank 2

21. Engine Control System Air Injection System Location -W -Q -V -C -A
Air Injection Control Valve (Bank 1)
Air Switching Valve
Air Pressure Sensor
Air Injection Control Valve (Bank 2)
Air Switching Valve
Air Pressure Sensor
Inlet
Front
Electric Air Pump (Bank 1)
Electric Air Pump (Bank 2)

22. Engine Control System Air Injection System Location -W -Q -V -C -A
Air Injection Control Driver (Bank 1)
Air Injection Control Driver (Bank 2)

23. Engine Control System Air Injection System-W -Q -V -C -A
Air Injection System
Electric air pump supplies air into the air injection control valve
Air Filter
(Maintenance Free)
Impeller
Electric air pump consists of a DC motor, impeller and air filter.
Electric air pump supplies air into the air injection control valve through the impeller.
The air filter is maintenance-free.
Electric Air Pump (Bank 1)
DC Motor
Electric Air Pump (Bank 2)

24. Air Injection Control Valve
Engine Control System -W -Q -V -C -A
Air Injection System
Air injection control valve consists of an air switching valve that switches the air ON/OFF to the exhaust ports
Air Injection Control Valve
For Bank 1
For Bank 2
Air Pressure Sensor
Air Switching Valve
Air injection control valve consists of an air switching valve, reed valve, and air pressure sensor.
Air switching valve switches the air ON/OFF to the exhaust ports.
The reed valve prevents back-blow from the exhaust port.
Air pressure sensor is used to monitor the air injection system and to detect a malfunction.
Reed Valve

25. Engine Control System Air Injection System-W -Q -V -C -A
Air Injection System
Air injection control driver actuates electric air pump and air switching valve
ECM
Electric Air Pump Actuation Request
AIRP
SIP
Air Injection Control Driver (Bank 1)
Air Switching Valve Actuation Request
AIRV
SIV
AIDI
Failure Status (Duty) DI
Air injection control driver actuates electric air pump and air switching valve in accordance with the signal from ECM.
ARP2
SIP2
Air Injection Control Driver (Bank2)
Electric Air Pump (Bank 1)
ARV2
SIV2
Air Switching Valve (Bank 1)
AID2
DI2

26. Duty Ratio (Duty Signal)
Engine Control System -W -Q -V -C -A
Air Injection System
Air injection control driver transmits failure status to ECM via duty cycle signal from DI terminal
Conditions
Duty Ratio (Duty Signal)
Normal A B
Failure Status
Open circuit in between AIDI and DI terminal 
Failure in line between ECM and air injection driver terminals
Failure in electric air pump actuation circuit
Failure in air injection control valve circuit
Overheat failure of air injection driver
80%
20% +B
GND +B 0%
GND +B
100%
GND +B 0%
GND
Air injection driver transmits failure status to ECM via duty cycle signal from DI terminal.
20% +B
GND
40% +B
GND
60% +B
GND
A: Electric air pump and air injection control valve are actuating
B: Conditions other than A

27. Reference (Engine Control System)-W -Q -V -C -A
Air Injection System
DTCs for air injection system (1/2)
DTC
Trouble area
P0412
Secondary Air Injection System Air Switching Value “A” Circuit
P0415
Secondary Air Injection System Air Switching Valve "B" Circuit
P0418
Secondary Air Injection System Control "A" Circuit
P0419
Secondary Air Injection System Control "B" Circuit
P1613
Air Injection System Air Injection Driver Bank 1
P1614
Air Injection System Air Injection Driver Bank 2
P2431
Secondary Air Injection System Air Flow/Pressure Sensor Circuit Range/Performance Bank 1
P2432
Secondary Air Injection System Air Flow/Pressure Sensor Circuit Low Bank 1
P2433
Secondary Air Injection System Air Flow/Pressure Sensor Circuit High Bank 1
P2436
Secondary Air Injection System Air Flow/Pressure Sensor Circuit Range/Performance Bank 2
P2437
Secondary Air Injection System Air Flow/Pressure Sensor Circuit Low Bank 2
P2438
Secondary Air Injection System Air Flow/Pressure Sensor Circuit High Bank 2
There are 20 DTCs for AI system.

28. Reference (Engine Control System)-W -Q -V -C -A
Air Injection System
DTCs for air injection system (2/2)
DTC
Trouble area
P2440
Secondary Air Injection System Switching Value Stuck Open Bank 1
P2441
Secondary Air Injection System Switching Value Stuck Closed Bank 1
P2442
Secondary Air Injection System Switching Value Stuck Open Bank 2
P2443
Secondary Air Injection System Switching Value Stuck Closed Bank 2
P2444
Secondary Air Injection System Pump Stuck On Bank 1
P2445
Secondary Air Injection System Pump Stuck Off Bank 1
P2446
Secondary Air Injection System Pump Stuck On Bank 2
P2447
Secondary Air Injection System Pump Stuck Off Bank 2
If the Reed valve is stuck closed DTC P2441/P2443 will be set.

29. Engine Control System Fuel Pump Control-W -Q -V -C -A
Fuel Pump Control
Fuel pump ECU controls the fuel pump speed in 3 steps Fr
Fuel Pump ECU
Fuel pump ECU controls the fuel pump speed in 3 steps.
Decrease fuel pump noise and increase fuel pump life by lower voltage fuel pump control.
Reduce evaporative emission by lower fuel pump heating.
Increase fuel economy by PWM control.

30. Fuel Pump Operation Signal
Engine Control System -W -Q -V -C -A
Fuel Pump Control
Hi:
Mid:
Lo:
OFF: +B 0V
12 msec
ECM
Engine Speed
Injection Volume
Fuel Pump Operation Signal
Fuel Pump ECU
FP+
FPC
FPC
Fuel pump ECU controls the fuel pump speed in 3 steps in accordance with the operation signal (duty signal) from ECM (Hi, Mid, Lo or OFF).
- When the engine starts or carries heavy loads with engine speed high, the ECM sends a Hi signal.
- When the engine carries heavy loads with engine speed low, the ECM sends a Mid signal.
- When the engine is idling or carries a light load, the ECM sends a Lo signal.
Fuel pump ECU has a diagnosis function. When a malfunction (open / short circuit, overheat or overcurrent) is detected during the pump operation, fuel pump ECU outputs abnormal signal (0V) from the DI terminal.
Note: The details of the malfunction cannot be known from the diagnosis signal.
While the fuel pump is not operating (FPC input “OFF”), fuel pump ECU outputs 0V from the DI terminal. M
Diagnosis Signal
Fuel Pump DI DI
FP-
Normal: 10V
Abnormal: 0V

31. Engine Control System ECM Dash panel penetration installation -W -Q -V
Body
ECM
ECM
Dash panel penetration installation is adopted a countermeasure for heat.
ECM with waterproof connector.
Note: This vehicle uses a fluid coupler driven cooling fan. This system does not control heat in the engine compartment as well as electric cooling fans therefore the ECM is in the cab area for temperature control and the connector is in the engine compartment so that the wire harness does not have to route through the dash panel.
Gasket
(Non-reusable Part)