EC-218
< COMPONENT DIAGNOSIS >[VK56DE]
P0420, P0430 THREE WAY CATALYST FUNCTION
NG >> GO TO 7.
7.CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a known-good spark plug.
3. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and the grounded metal portion.
OK or NG
OK >> GO TO 8.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-411, "
Diagnosis Procedure".
8.CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.
OK or NG
OK >> Replace malfunctioning spark plug(s) with standard type one(s). For spark plug type, refer to EM-16, "
Removal
and Installation".
NG >> 1. Repair or clean spark plug. 2. GO TO 9.
9.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about three seconds, and recheck whether spark is generated between the spark plug
and the grounded portion.
OK or NG
OK >> INSPECTION END
NG >> Replace malfunctioning spark plug(s) with standard type one(s). For spark plug type, refer to EM-
16, "Removal and Installation".
10.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly. Refer to EM-40, "
Removal and Installation".
Keep fuel hose and all fuel injectors connected to fuel injector gallery.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON. Make sure fuel does not drip from fuel injector.
OK or NG
OK (Does not drip.)>>GO TO 11.
NG (Drips.)>>Replace the fuel injector(s) from which fuel is dripping.
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
Trouble is fixed.>> INSPECTION END
Trouble is not fixed.>>Replace three way catalyst assembly. Spark should be generated.
SEF156I
Spark should be generated.
Revision: March 2010
2008 QX56
EC-488
< PRECAUTION >[VK56DE]
PRECAUTIONS
•
When connecting ECM harness co nnector, fasten it securely
with a lever as far as it will go as shown in the figure.
• When connecting or disconnect ing pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
• Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) volt-
age to develop in coil and co ndenser, thus resulting in dam-
age to ICs.
• Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to preven t engine control system mal-
functions due to receiving external noise, degraded operation
of ICs, etc.
• Keep engine control system parts and harness dry.
• Before replacing ECM, perform ECM Terminals and Reference
Value inspection and make sure ECM functions properly.
Refer to EC-429, "
ECM Terminal and Reference Value".
• Handle mass air flow sensor carefully to avoid damage.
• Do not disassemble m ass air flow sensor.
• Do not clean mass air flow sensor with any type of detergent.
• Do not disassemble electric throttle control actuator.
• Even a slight leak in the ai r intake system can cause serious
incidents.
• Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
• After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displ ayed in the DTC Confirmation
Procedure if the repair is co mpleted. The Overall Function
Check should be a good result if the repair is completed.
BBIA0387E
PBIB0090E
MEF040D
SEF217U
Revision: March 2010 2008 QX56
EM-1
ENGINE
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SECTION EM
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CONTENTS
ENGINE MECHANICAL
PRECAUTION ....... ........................................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
3
Precaution for Drain Engine Coolant .........................4
Precaution for Disconnecting Fuel Piping .................4
Precaution for Removal and Disassembly ................4
Precaution for Inspection, Repair and Replace-
ment .................................................................... ......
4
Precaution for Assembly and Installation ..................4
Parts Requiring Angular Tightening ..........................4
Precaution for Liquid Gasket ............................... ......5
PREPARATION ............................................6
PREPARATION .............................................. .....6
Special Service Tool ........................................... ......6
Commercial Service Tool ..........................................8
FUNCTION DIAGNOSIS ..............................10
NOISE, VIBRATION, AND HARSHNESS
(NVH) TROUBLESHOOTING ........................ ....
10
NVH Troubleshooting - Engine Noise ................. ....10
Use the Chart Below to Help You Find the Cause
of the Symptom .......................................................
11
ON-VEHICLE MAINTENANCE ....................13
DRIVE BELTS ................................................ ....13
Checking Drive Belts ........................................... ....13
Removal and Installation .........................................13
Drive Belt Auto Tensioner and Idler Pulley ......... ....14
AIR CLEANER FILTER ......................................15
Removal and Installation (Viscous paper type) ... ....15
SPARK PLUG ................................................ ....16
Removal and Installation ..................................... ....16
CAMSHAFT VALVE CLEARANCE ..................18
Valve Clearance ......................................................18
COMPRESSION PRESSURE ...........................23
Checking Compression Pressure ............................23
ON-VEHICLE REPAIR .................................24
ENGINE ROOM COVER ...................................24
Removal and Installation ..................................... ....24
AIR CLEANER AND AIR DUCT .......................25
Removal and Installation .........................................25
INTAKE MANIFOLD .........................................26
Removal and Installation .........................................26
EXHAUST MANIFOLD AND THREE WAY
CATALYST ........................................................
30
Exploded View .........................................................30
Removal and Installation .........................................30
OIL PAN AND OIL STRAINER .........................33
Removal and Installation .........................................33
IGNITION COIL .................................................37
Removal and Installation .........................................37
ROCKER COVER .............................................38
Removal and Installation .........................................38
FUEL INJECTOR AND FUEL TUBE ................40
Removal and Installation .........................................40
TIMING CHAIN ..................................................44
Components ........................................................ ....44
Removal and Installation .........................................45
CAMSHAFT .......................................................53
Components ............................................................53
Removal and Installation .........................................53
Revision: March 2010 2008 QX56
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTINGEM-11
< FUNCTION DIAGNOSIS >
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Use the Chart Below to Help You
Find the Cause of the SymptomINFOID:0000000001538804
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
1. Timing chain 2. Intake valve3. Exhaust valve
4. Drive belt 5. Water pumpA. VTC noise
B. Tappet noise C. Camshaft bearing noiseD. Valve mechanism
E. Rotation mechanism F. Piston pin noise G. Piston slap noise
H. Main bearing noise I. Connecting rod bearing noise J. Drive belt noise (slipping)
K. Drive belt noise (stick/slipping) L. Water pump noise M. Timing chain and chain tensioner noise
Location of noise Ty p e o f
noise Operating condition of engine
Source of noise Check item Refer-
ence page
Be-
fore
warm-
up After
warm- up When
start- ing When
idling When
racing While
driv- ing
Top of en-
gine
Rocker cov-
er
Cylinder
head Ticking or
clicking
C A — A B — Tappet noise Valve clearance
EM-18
Rattle C A — A B CCamshaft
bearing noiseCamshaft journal clear-
ance
Camshaft runout EM-53EM-53
Crankshaft
pulley
Cylinder
block (Side
of engine)
Oil panSlap or
knock
—A—B B—
Piston pin
noisePiston and piston pin
clearance
Connecting rod bushing
clearance
EM-90
EM-90
Slap or
rap
A——B B A
Piston slap
noisePiston-to-bore clear-
ance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsion EM-90EM-90
EM-90
EM-90
Knock A B C B B B
Connecting
rod bearing
noiseConnecting rod bushing
oil clearance (Small
end)
Connecting rod bearing
clearance (Big end)
EM-90EM-90
Knock A B — A B C
Main bearing
noiseMain bearing oil clear-
ance
Crankshaft runout EM-90EM-90
Front of en-
gine
Chain case
cover
Front coverTapping
or ticking
AA—BBB Timing chain
and chain
tensioner
noiseTiming chain cracks
and wear
Timing chain tensioner
operation
EM-45
EM-45
Revision: March 2010
2008 QX56
ENGINE ASSEMBLYEM-79
< REMOVAL AND INSTALLATION >
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4. Remove the engine hood. Refer to
DLK-224, "Removal and Installation of Hood Assembly".
5. Remove the cowl extension. Refer to EXT-18, "
Removal and Installation".
6. Remove the engine room cover using power tools.
7. Remove the air duct and air cleaner case assembly. Refer to EM-25, "
Removal and Installation".
8. Disconnect the vacuum hose between the vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-15, "
Removal and Installation".
10. Remove the drive belts. Refer to EM-13, "
Removal and Installation".
11. Remove the fan blade. Refer to CO-18, "
Removal and Installation (Crankshaft Driven Type)".
12. Disconnect the engine room harness from the fuse box and set it aside.
13. Disconnect the ECM.
14. Disconnect the engine room harness from the engine side and set it aside.
15. Disconnect the engine harness grounds.
16. Disconnect the power steering reservoir t ank from the engine and move it aside.
17. Disconnect the power steering oil pump from the engine. Move it aside and secure it using suitable wire or rope. Refer to ST-26, "
Removal and Installation".
18. Remove the A/C compressor bolts and set the compressor aside. Refer to HA-31, "
Removal and Installa-
tion for Compressor" (ATC).
19. Disconnect the brake booster vacuum line.
20. Disconnect the EVAP line.
21. Disconnect the fuel hose at the engine side connection. Refer to EM-40, "
Removal and Installation".
22. Disconnect the heater hoses at the cowl, and in stall plugs to avoid leakage of engine coolant.
23. Remove the A/T oil level indicator and indicator tube upper bolts.
24. Remove the front final drive assembly (4WD only). Refer to DLN-212, "
Removal and Installation".
25. Remove the exhaust manifolds. Refer to EM-30, "
Removal and Installation".
26. Install the engine slingers into the left bank cylinder head and right bank cylinder head.
27. Remove the A/T. Refer to TM-214, "
Removal and Installation
(2WD)" or TM-216, "Removal and Installation (4WD)" .
28. Lift using a hoist and secure the engine in position.
29. Remove the engine assembly from the vehicle, avoid interfer- ence with the vehicle body.
CAUTION:
• Before and during lifting, always check if any harnessesare left connected.
30. Remove the parts that may restrict installation of the engine to the engine stand. NOTE:
This procedure is described assuming that you use an engine stand mounting to the surface to which the
transmission mounts.
WBIA0795E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
WBIA0715E
Revision: March 2010 2008 QX56
ENGINE UNITEM-83
< DISASSEMBLY AND ASSEMBLY >
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DISASSEMBLY
NOTE:
Explained here is how to disassemble with engine stand supporting transmission surface. When using differ-
ent type of engine stand, some steps may be different.
1. Remove engine assembly and mount to engine stand. Refer to
EM-78, "
Removal and Installation".
CAUTION:
Before removing the hanging chains, make sure engi ne stand is stable and there is no risk of over-
turning.
2. Drain engine oil. Refer to LU-9, "
Changing Engine Oil".
3. Drain engine coolant by removing the cylinder block drain plugs “A”, “B”, “C” and “D” as shown.
4. Remove the following components and associated parts (the parts referred to in step 1 are not included here).
• Oil pan (upper and lower) and oil strainer. Refer to EM-33, "
Removal and Installation".
• Crankshaft pulley, front cover and timing chain. Refer to EM-45, "
Removal and Installation".
• Camshaft. Refer to EM-53, "
Removal and Installation".
• Cylinder head. Refer to EM-68, "
Removal and Installation".
5. Remove knock sensor and sub harness. CAUTION:
Carefully handle sensor, avoiding shocks.
6. Check connecting rod side clearance. Refer to EM-90, "
Inspection After Disassembly".
7. Remove piston and connecting rod assembly as follows.
a. Position the crankshaft pin corresponding to the connecting rod to be removed onto bottom dead center.
b. Remove connecting rod cap.
16. Thrust bearing lower 17. Main bearing lower18. Crankshaft
19. Pilot converter 20. Thrust bearing upper21. Side bolt
22. Drive plate 23. Reinforcement plate24. Rear oil seal retainer
25. Rear oil seal 26. Transmission27. O-ring
28. Crankshaft position sensor (POS) 29. Gasket 30. Cylinder block heater
31. Connector cap
WBIA0419E
KBIA2549E
Revision: March 2010 2008 QX56
EM-86
< DISASSEMBLY AND ASSEMBLY >
ENGINE UNIT
ASSEMBLY
1. Fully air-blow the coolant and oil passages in the cylinder block, cylinder bore, and crankcase to removeany foreign material.
CAUTION:
Use goggles to protect your eyes.
2. Install each plug to the cylinder block (only screw-type plugs are shown).
• Apply liquid gasket. Use Genuine Thread Sealant or equivalent. Refer to GI-15,
"Recommended Chemical Products and Sealants".
• Replace copper washers with new ones.
• Tighten each plug as specified below.
3. Install main bearings and thrust bearings.
a. Remove any dust, dirt, and oil on the bearing mating surfaces of the cylinder block and main bearing caps.
b. Install thrust bearings to both sides of the No. 3 journal housing on the cylinder block and main bearing caps
• Install thrust bearings with the oil groove facing the crankshaft
arm (outside).
• Install thrust bearings with a protrusion in the center on the
main bearing caps.
c. Install main bearings paying attention to the direction. • Install the one with oil holes onto the cylinder block and theone without oil holes onto the main bearing cap.
• Before installing bearings, apply engine oil to bearing surface
(inside). Do not apply oil to the back surface, but thoroughly
clean it.
• When installing, align the bearing stopper to the notch.
• Ensure the oil holes on the cylinder block and those on the
corresponding bearing are aligned.
4. Install pilot converter to the crankshaft using suitable tool.
5. Install crankshaft to the cylinder block. • While turning crankshaft by hand, make sure it turns smoothly.
Part Washer Tightening torque
A Yes 53.9 N·m (5.5 kg-m, 40 ft-lb)
B No 19.6 N·m (2.0 kg-m, 15 ft-lb)
C Yes 62.7 N·m (6.4 kg-m, 46 ft-lb)
D Yes 62.7 N·m (6.4 kg-m, 46 ft-lb)
WBIA0419E
PBIC0093E
PBIC0094E
EMP0569D
Revision: March 2010 2008 QX56
HEADLAMPEXL-7
< FUNCTION DIAGNOSIS >
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FUNCTION DIAGNOSIS
HEADLAMP
System DiagramINFOID:0000000001547094
System DescriptionINFOID:0000000001547095
Control of the headlamp system operation is dependent upon the position of the lighting switch (combination
switch). When the lighting switch is placed in the 2nd position, the BCM (body control module) receives input
requesting the headlamps and park lamps to illuminate. Th is input is communicated to the IPDM E/R (intelli-
gent power distribution module engine room) via the CA N communication lines. The CPU (central processing
unit) of the IPDM E/R controls the headlamp high and headl amp low relay coils. When energized, these relays
direct power to the respective headlamps, which then illuminate.
Component Parts LocationINFOID:0000000001547096
Component DescriptionINFOID:0000000001547097
XENON HEADLAMP
A Xenon type headlamp is adapted to the low beam headlamps. Xenon bulbs do not use a filament.
Instead,they produce light when a high voltage current is passed between two tungsten electrodes through a
AWLIA0009GB
1. BCM M18, M20 (view with instrument
panel removed) 2. IPDM E/R E122, E123, E124 3. Combination switch M28
4. Combination meter M23, M24
ALLIA0379ZZ
Revision: March 2010 2008 QX56