Crankshaft position INFINITI QX4 2001 Factory Repair Manual

System DescriptionNBEC0392
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed (POS signal)
Fuel pump
controlFuel pump relay Crankshaft position sensor (REF) Engine speed (REF signal)
Ignition switch Start signal
The ECM activates the fuel pump for several seconds after the ignition switch is turned on to improve engine
startability. If the ECM receives a 120É signal from the crankshaft position sensor (REF), it knows that the
engine is rotating, and causes the pump to operate. If the 120É signal is not received when the ignition switch
is on, the engine stalls. The ECM stops pump operation and prevents battery discharging, thereby improving
safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump relay, which in turn
controls the fuel pump.
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and cranking Operates.
When engine is stopped Stops in 1.5 seconds.
Except as shown aboveStops.
SEF018S
Component DescriptionNBEC0393The fuel pump with a fuel damper is an in-tank type (the pump and
damper are located in the fuel tank).
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0394Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL PUMP RLYIIgnition switch is turned to ON. (Operates for 1 second.)
IEngine running and crankingON
Except as shown above OFF
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FUEL PUMP
System Description
EC-625

Throttle Position SensorNBEC0419
Throttle valve conditionsVoltage
(at normal operating temperature,
engine off, ignition switch ON,
throttle opener disengaged)
Completely closed (a)0.15 - 0.85V
Partially openBetween (a) and (b)
Completely open (b)3.5 - 4.7V
Calculated Load ValueNBEC0420
Calculated load value % (Using CONSULT-II or GST)
At idle14.0 - 33.0
At 2,500 rpm12.0 - 25.0
Intake Air Temperature SensorNBEC0421
Temperature ÉC (ÉF) Resistance kW
20 (68)2.1 - 2.9
80 (176)0.27 - 0.38
Heated Oxygen Sensor 2 Heater (Rear)NBEC0422
Resistance [at 25ÉC (77ÉF)]2.3 - 4.3W
Crankshaft Position Sensor (REF)NBEC0423
Resistance [at 20ÉC (68ÉF)]470 - 570W
Fuel Tank Temperature SensorNBEC0424
Temperature ÉC (ÉF) Resistance kW
20 (68)2.3 - 2.7
50 (122)0.79 - 0.90
Camshaft Position Sensor (PHASE)NBEC0639
Resistance [at 20ÉC (68ÉF)]HITACHI make 1,440 - 1,760W
MITSUBISHI make 2,090 - 2,550W
SERVICE DATA AND SPECIFICATIONS (SDS)
Throttle Position Sensor
EC-650

Code Section Wiring Diagram Name
NAVI EL Navigation System
NONDTC AT Non-detectable Items
O2H1B1 EC Heated Oxygen Sensor 1 Heater
(Front) (Bank 1)
O2H1B2 EC Heated Oxygen Sensor 1 Heater
(Front) (Bank 2)
O2H2B1 EC Heated Oxygen Sensor 2 Heater
(Rear) (Bank 1)
O2H2B2 EC Heated Oxygen Sensor 2 Heater
(Rear) (Bank 2)
O2S1B1 EC Heated Oxygen Sensor 1 (Front)
(Bank 1)
O2S1B2 EC Heated Oxygen Sensor 1 (Front)
(Bank 2)
O2S2B1 EC Heated Oxygen Sensor 2 (Rear)
(Bank 1)
O2S2B2 EC Heated Oxygen Sensor 2 (Rear)
(Bank 2)
OVRCSV AT Overrun Clutch Solenoid Valve
P/ANT EL Power Antenna
PGC/V EC EVAP Canister Purge Volume
Control Solenoid Valve
PHASE EC Camshaft Position Sensor
(PHASE)
PNP/SW EC Park/Neutral Position Switch
PNP/SW AT Park/Neutral Position Switch
POS EC Crankshaft Position Sensor
(CKPS) (POS)
POWER EL Power Supply Routing
PRE/SE EC EVAP Control System Pressure
Sensor
PST/SW EC Power Steering Oil Pressure
Switch
REF EC Crankshaft Position Sensor
(CKPS) (REF)
REMOTE EL Audio (Remote Control Switch)
RP/SEN EC Refrigerant Pressure
S/SIG EC Start Signal
S/VCSW EC Swirl Control Valve Control
Vacuum Check Switch
SEAT EL Power Seat
SHIFT AT A/T Shift Lock System
SROOF EL Sunroof
SRS RS Supplemental Restraint SystemCode Section Wiring Diagram Name
SSV/A AT Shift Solenoid Valve A
SSV/B AT Shift Solenoid Valve B
START SC Starting System
STOP/L EL Stop lamp
SWL/V EC Swirl Control Valve Control Sole-
noid Valve
TAIL/L EL Parking, License and Tail Lamps
TCCSIG AT A/T TCC Signal (Lock up)
TCV AT Torque Converter Clutch Solenoid
Valve
T/F TF Transfer
TFTS EC Tank Fuel Temperature Sensor
THEFT EL Theft Warning System
TLID EL Glass Hatch Opener
TP/SW EC Throttle Position Switch
TPS AT Throttle Position Sensor
TPS EC Throttle Position Sensor
TRNSMT EL Integrated HOMELINKYTrans-
mitter
TRSA/T AT Turbine Revolution Sensor
TURN EL Turn Signal and Hazard Warning
Lamps
VIAS/V EC Variable Induction Air Control Sys-
tem
VSS EC Vehicle Speed Sensor
VSSA/T AT Vehicle Speed Sensor A/T (Revo-
lution Sensor)
VSSMTR AT Vehicle Speed Sensor MTR
WARN EL Warning Lamps
WINDOW EL Power Window
WIP/R EL Rear Wiper and Washer
WIPER EL Front Wiper and Washer
WIRING DIAGRAM CODES (CELL CODES)
EL-458

ENGINE MECHANICAL
SECTION
EM
CONTENTS
PRECAUTIONS...............................................................3
Parts Requiring Angular Tightening .............................3
Liquid Gasket Application Procedure ..........................3
PREPARATION...............................................................4
Special Service Tools ..................................................4
Commercial Service Tools ...........................................6
NOISE, VIBRATION AND HARSHNESS (NVH)
TROUBLESHOOTING.....................................................8
NVH Troubleshooting - Engine Noise .........................9
OUTER COMPONENT PARTS.....................................10
Removal and Installation ...........................................10
TIGHTENING PROCEDURES...................................12
MEASUREMENT OF COMPRESSION PRESSURE....14
OIL PAN.........................................................................15
Components...............................................................15
Removal .....................................................................15
Installation ..................................................................18
TIMING CHAIN..............................................................20
Components...............................................................20
POSITION FOR APPLYING LIQUID GASKET............21
Removal .....................................................................23
Inspection...................................................................29
Installation ..................................................................29
OIL SEAL.......................................................................35
Replacement ..............................................................35
VALVE OIL SEAL.....................................................35
OIL SEAL INSTALLATION DIRECTION.....................36
FRONT OIL SEAL....................................................36
REAR OIL SEAL......................................................36
CYLINDER HEAD..........................................................38
Components...............................................................38
Removal .....................................................................39
Disassembly...............................................................41
Inspection...................................................................42
CYLINDER HEAD DISTORTION...............................42
CAMSHAFT VISUAL CHECK....................................42
CAMSHAFT RUNOUT..............................................42
CAMSHAFT CAM HEIGHT.......................................42
CAMSHAFT JOURNAL CLEARANCE........................42
CAMSHAFT END PLAY............................................43
CAMSHAFT SPROCKET RUNOUT...........................43
VALVE GUIDE CLEARANCE....................................43
VALVE GUIDE REPLACEMENT................................44
VALVE SEATS.........................................................45
REPLACING VALVE SEAT FOR SERVICE PARTS....45
VALVE DIMENSIONS...............................................46
VALVE SPRING.......................................................46
VALVE LIFTER........................................................46
Assembly ...................................................................47
Installation ..................................................................47
Valve Clearance.........................................................52
CHECKING.............................................................52
ADJUSTING............................................................54
ENGINE ASSEMBLY.....................................................57
Removal and Installation ...........................................57
REMOVAL...............................................................58
INSTALLATION........................................................60
CYLINDER BLOCK.......................................................61
Components...............................................................61
CYLINDER BLOCK HEATER....................................62
Removal and Installation ...........................................62
Disassembly...............................................................62
PISTON, CRANKSHAFT AND OIL JET......................62
Inspection...................................................................63
PISTON AND PISTON PIN CLEARANCE..................63
PISTON RING SIDE CLEARANCE............................64
PISTON RING END GAP..........................................64
CONNECTING ROD BEND AND TORSION...............65
CYLINDER BLOCK DISTORTION AND WEAR...........65
PISTON-TO-BORE CLEARANCE..............................66
CRANKSHAFT.........................................................67
BEARING CLEARANCE...........................................67
CONNECTING ROD BUSHING CLEARANCE
(SMALL END)
..........................................................70
DRIVE PLATE RUNOUT..........................................70
Assembly ...................................................................71
PISTON..................................................................71
OIL JET..................................................................71
CRANKSHAFT.........................................................71
REPLACEMENT OF PILOT CONVERTER.................74
DRIVE PLATE.........................................................74
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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

SEM421G
SEM422G
13. Remove camshaft position sensor (PHASE), CVTC sensors
and crankshaft position sensor (REF).
IAvoid impact such as dropping.
IDo not disassemble the components.
IDo not place them on areas where iron powder may adhere.
IKeep away from the objects susceptible to magnetism.
SEM412G
14. Remove upper intake manifold collector in reverse order of
installation. Refer to EM-12, ªUpper Intake Manifold Collectorº.
SEM413G
15. Remove intake manifold collector support bolts.
SEM414G
16. Remove lower intake manifold collector in reverse order of
installation. Refer to EM-13, ªLower Intake Manifold Collectorº.
TIMING CHAIN
Removal (Cont'd)
EM-24

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

SEM439G
SEM440G
17. Install RH and LH rocker covers.
Rocker cover tightening procedure:
ITighten in numerical order as shown in the figure.
a. Tighten bolts 1 to 10 in that order to 6.9 to 8.8 N´m (0.7 to 0.9
kg-m, 61 to 78 in-lb).
b. Then tighten bolts 1 to 10 as indicated in figure to 6.9 to 8.8
N´m (0.7 to 0.9 kg-m, 61 to 78 in-lb).
18. Hang engine using the right and left side engine slingers with
a suitable hoist.
19. Set a suitable transmission jack under the suspension mem-
ber.
20. Remove right and left side engine mounting nuts.
21. Remove right and left side suspension member bolts.
22. Install aluminum oil pan. Refer to EM-18, ªInstallationº.
23. Set ring gear stopper using the mounting bolt hole.
IBe careful not to damage the signal plate teeth.
SEM417G
24. Install crankshaft pulley to crankshaft.
IAlign pointer with TDC mark on crankshaft pulley.
SEM531G
25. Install crankshaft pulley bolt.
ILubricate thread and seat surface of the bolt with new
engine oil.
a. Tighten to 39 to 49 N´m (4.0 to 5.0 kg-m, 29 to 36 ft-lb).
b. Put a paint mark on the crankshaft pulley.
SEM963E
c. Again tighten by turning 60É to 66É, about the angle from one
hexagon bolt head corner to another.
26. Install camshaft position sensor (PHASE), crankshaft position
sensors (REF)/(POS) and CVTC sensors.
27. Reinstall removed parts in the reverse order of removal.
IWhen installing fuel tube and intake manifold collectors, refer
to EM-12, ªTIGHTENING PROCEDURESº.
IAfter starting engine, keep idling for three minutes. Then
rev engine up to 3,000 rpm under no load to purge air from
the high-pressure chamber of the chain tensioners. The
engine may produce a rattling noise. This indicates that
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TIMING CHAIN
Installation (Cont'd)
EM-33

SEM948E
ReplacementNBEM0015CAUTION:
When removing the oil pans, oil pump assembly and timing
chain from engine, first remove the camshaft position sensor
(PHASE), CVTC sensor and the crankshaft position sensors
(REF)/(POS) from the assembly.
Be careful not to damage sensor edges.
VALVE OIL SEALNBEM0015S011. Remove timing chain. Refer to ªRemoval, EM-23.
2. Remove camshaft brackets and camshaft. Refer to
ªDisassemblyº, EM-41.
3. Remove valve lifters and shims.
4. Remove valve spring with Tool.
5. Reinstall any parts removed in reverse order of removal.
Before removing valve spring, fix valve as follows.
Method A:
Piston concerned should be set at TDC to prevent valve
from falling.
SEM826E
Method B:
Remove spark plug, then install air hose adapter into
spark plug hole and apply air pressure to hold valves in
place. Apply a pressure of 490 kPa (5 kg/cm
2, 71 psi).
SEM983D
Method C:
Install spark plug with suitable washer into spark plug
hole from combustion chamber side.
SEM827E
6. Remove valve oil seal.
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OIL SEAL
Replacement
EM-35