engine INFINITI QX4 2001 Factory Service Manual

SEM484GA
1. Heated oxygen sensor 1 (front)
(bank 1)
2. Heated oxygen sensor 1 (front)
(bank 2)
3. TWC (manifold)4. Thermostat with water inlet
5. Exhaust manifold
6. Thermal transmitter
7. Engine coolant temperature8. Water control valve
9. Water outlet housing
10. Cylinder block water outlet
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OUTER COMPONENT PARTS
Removal and Installation (Cont'd)
EM-11

SEM950F
TIGHTENING PROCEDURESNBEM0006S01Intake ManifoldNBEM0006S0101ITighten in numerical order shown in the figure.
1. Tighten all bolts and nuts to 5 to 10 N´m (0.5 to 1.0 kg-m, 44
to 86 in-lb).
2. Finally tighten all bolts and nuts to 26 to 31 N´m (2.7 to 3.2
kg-m, 20 to 23 ft-lb).
ITighten all bolts and nuts to the final torque, evenly dividing the
tightening into at least five steps.
SEM473G
Fuel TubeNBEM0006S0102ITighten in numerical order shown in the figure.
1. Tighten all bolts to 9.3 to 10.8 N´m (0.95 to 1.1 kg-m, 83 to 95
in-lb).
2. Then tighten all bolts to 21 to 26 N´m (2.1 to 2.7 kg-m, 15 to
20 ft-lb).
SEM474G
Fuel Pressure RegulatorNBEM0006S0103Tighten fuel pressure regulator to 2.9 to 3.8 N´m (0.3 to 0.39 kg-m,
26.0 to 33.9 in-lb).
ITighten screws evenly several times to have the fuel pres-
sure regulator tightened at the specified torque.
IAlways replace O-ring with new ones.
ILubricate O-ring with new engine oil.
SEM475G
Throttle BodyNBEM0006S0105ITighten in numerical order shown in the figure.
1. Tighten all bolts to 8.8 to 10.8 N´m (0.9 to 1.1 kg-m, 79 to 95
in-lb).
2. Then tighten all bolts to 18 to 21 N´m (1.8 to 2.2 kg-m, 13 to
15 ft-lb).
SEM476G
Upper Intake Manifold CollectorNBEM0006S0107Tighten bolts and nuts to 18 to 21 N´m (1.8 to 2.2 kg-m, 13 to 15
ft-lb) in numerical order shown in the figure.
OUTER COMPONENT PARTS
Removal and Installation (Cont'd)
EM-12

NBEM0007
SEM480G
SEM481G
JEM482G
SEM387C
1. Warm up engine.
2. Turn ignition switch OFF.
3. Release fuel pressure.
Refer to EC-39, ªFuel Pressure Releaseº.
4. Remove engine cover and throttle wire.
5. Remove air duct with air cleaner case.
6. Remove harness connectors and harness brackets around
ignition coils.
7. Remove throttle body.
8. Disconnect ignition coil with power transistor harness
connectors, then remove ignition coils.
9. Remove all spark plugs.
IClean area around plug with compressed air before removing
the spark plug.
10. Attach a compression tester to No. 1 cylinder.
11. Depress accelerator pedal fully to keep throttle valve wide
open.
12. Crank engine and record highest gauge indication.
13. Repeat the measurement on each cylinder as shown above.
IAlways use a fully-charged battery to obtain specified
engine speed.
Unit: kPa (kg/cm2, psi)/rpm
Standard MinimumDifference limit between
cylinders
1,275 (13.0, 185)/300 981 (10.0, 142)/300 98 (1.0, 14)/300
14. If compression in one or more cylinders is low:
a. Pour a small amount of engine oil into cylinders through spark
plug holes.
b. Retest compression.
IIf adding oil helps compression, piston rings may be worn
or damaged. If so, replace piston rings after checking pis-
ton.
IIf pressure stays low, a valve may be sticking or seating
improperly. Inspect and repair valve and valve seat. (Refer
to SDS, EM-76 and EM-79.) If valve or valve seat is dam-
aged excessively, replace them.
IIf compression stays low in two cylinders that are next to
each other:
a) The cylinder head gasket may be leaking, or
b) Both cylinders may have valve component damage. Inspect
and repair as necessary.
15. Install parts in reverse order of removal.
16. Perform ªSelf-diagnosis Procedureº referring to EC-72, ªHow to
Erase DTCº if any DTC appears.
MEASUREMENT OF COMPRESSION PRESSURE
EM-14

ComponentsNBEM0008
SEM583G
RemovalNBEM0009WARNING:
IPlace vehicle on a flat and solid surface.
IYou should not remove oil pan until exhaust system and
cooling system have completely cooled off.
Otherwise, you may burn yourself and/or fire may break
out in the fuel line.
IWhen removing front engine mounting nuts, lift up slightly
engine for safety work.
CAUTION:
When removing the aluminum oil pan from engine, first
remove the crankshaft position sensors (POS and REF) from
the assembly.
Be careful not to damage sensor edges and signal plate teeth.
1. Remove front RH and LH wheels.
2. Remove battery.
3. Remove oil level gauge.
4. Remove engine undercover.
5. Remove suspension member stay.
6. Drain engine coolant from radiator drain plug.
7. Disconnect A/T oil cooler hoses.
8. Drain engine oil.
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OIL PAN
Components
EM-15

9. Remove the crankshaft position sensors (REF and POS).
10. Remove drive belts and idler pulley with bracket.
11. Remove power steering oil pump, then put it aside holding with
a suitable wire.
12. Remove alternator.
SEM605G
13. Install engine slingers.
14. Remove front propeller shaft. (4WD)
Refer to PD-6, ªRemoval and Installationº.
15. Remove exhaust front tube heat insulators, then remove rear
heat oxygen sensors.
16. Remove exhaust front tube from both sides.
Refer to FE-8, ªRemoval and Installationº.
17. Remove front final drive. (4WD)
Refer to PD-18, ªRemoval and Installationº.
18. Remove starter motor.
19. Disconnect oil pressure switch harness connector.
SEM528G
20. Loosen and disconnect the bolts fixing the steering column
assembly lower joint and the power steering gear.
SEM471G
21. Set a suitable transmission jack under the front suspension
member and hoist engine with engine slingers.
EMQ0357D
22. Remove front engine mounting nuts from both sides.
OIL PAN
Removal (Cont'd)
EM-16

SEM529G
SEM530G
23. Remove front suspension member bolts.
24. Lower the transmission jack carefully to secure clearance
between the oil pan and suspension member.
25. Remove A/T oil cooler tube.
26. Remove water hose and tube.
SEM469G
27. Remove the four engine-to-transmission bolts.
SEM463G
28. Remove aluminum oil pan bolts in numerical order.
SEM365E
29. Remove aluminum oil pan.
a. Insert tool between aluminum oil pan and cylinder block.
IBe careful not to damage aluminum mating surface.
IDo not insert screwdriver, or oil pan flange will be
deformed.
b. Slide tool by tapping its side with a hammer.
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OIL PAN
Removal (Cont'd)
EM-17

SEM159F
4. Apply a continuous bead of liquid gasket to mating surface of
aluminum oil pan.
IUse Genuine RTV silicone sealant Part No. 999MP-A7007
or equivalent.
SEM467G
5. Apply liquid gasket to inner sealing surface as shown in figure.
IBe sure liquid gasket is 4.0 to 5.0 mm (0.157 to 0.197 in)
or 4.5 to 5.5 mm (0.177 to 0.217 in) wide.
IAttaching should be done within 5 minutes after coating.
SEM464G
6. Install O-rings, cylinder block and oil pump body.
SEM468G
7. Install aluminum oil pan.
ITighten bolts in numerical order.
IWait at least 30 minutes before refilling engine oil.
SEM469G
8. Install the four engine-to-transmission bolts. For tightening
torque, refer to AT-278, ªInstallationº.
9. Reinstall in the revrse order of removal.
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OIL PAN
Installation (Cont'd)
EM-19

CAUTION:
IAfter removing timing chain, do not turn crankshaft and
camshaft separately, or valves will strike piston heads.
IWhen installing camshafts, chain tensioners, oil seals, or
other sliding parts, lubricate contacting surfaces with new
engine oil.
IApply new engine oil to bolt threads and seat surfaces
when installing camshaft sprockets and crankshaft pulley.
IBefore disconnecting fuel hose, release fuel pressure.
Refer to EC-39, ªFuel Pressure Releaseº.
IBe careful not to damage sensor edges.
IDo not spill engine coolant on drive belts.
RemovalNBEM00121. Release fuel pressure.
Refer to EC-39, ªFuel Pressure Releaseº.
2. Remove battery.
3. Remove radiator.
Refer to LC-19, ªREMOVAL AND INSTALLATIONº.
4. Drain engine oil.
5. Remove drive belts and idler pulley with brackets.
6. Remove cooling fan with bracket.
7. Remove engine cover.
8. Remove air duct with air cleaner case, collector, blow-by hose,
vacuum hoses, fuel hoses, water hoses, wires, harnesses,
connectors and so on.
9. Remove the air compressor, and tie it down using rope or the
like to keep it from interfering.
10. Remove the power steering oil pump and reservoir tank. Tie
them down using rope or the like to keep them from interfer-
ing.
11. Remove alternator.
12. Remove the following.
IVacuum gallery
IWater bypass pipe
IBrackets
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TIMING CHAIN
Components (Cont'd)
EM-23

SEM419G
23. Loosen the crankshaft pulley bolt.
SEM420G
24. Remove crankshaft pulley with a suitable puller.
25. Remove aluminum oil pan.
Refer to EM-15, ªRemovalº.
26. Temporarily install the suspension member bolts and engine
mounting nuts.
SEM423G
27. Remove CVTC covers.
ILoosen bolts in numerical order as shown in the figure.
IIn the cover, the shaft is engaged with the center hole of the
intake cam sprocket. Remove it straight out until the engage-
ment comes off.
SEM424G
28. Remove front timing chain case bolts.
ILoosen bolts in numerical order as shown in the figure.
SEM156F
29. Remove front timing chain case.
IDo not scratch sealing surfaces.
TIMING CHAIN
Removal (Cont'd)
EM-26

SEM928E
InspectionNBEM0013Check for cracks and excessive wear at roller links. Replace
chain if necessary.
SEM930E
InstallationNBEM00141. Position crankshaft so that No. 1 piston is set at TDC on com-
pression stroke.
SEM929E
2. Install crankshaft sprocket on crankshaft.
IMake sure that mating marks on crankshaft sprocket face
front of engine.
SEM931E
3. Install lower chain guide on dowel pin, with front mark on the
guide facing upside.
SEM430G
4. Press and shrink the secondary chain tensioner sleeve, and fix
it using stopper pins.
ILubricate threads and seat surfaces of camshaft sprocket bolts
with new engine oil.
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TIMING CHAIN
Inspection
EM-29