2001 INFINITI QX4 Crankshaft position

IBefore assembly, apply a coat of recommended ATF to all
parts. Apply petroleum jelly to protect O-rings and seals, or
hold bearings and washers in place during assembly. Do not
use grease.
IExtreme care should be taken to avoid damage to O-rings,
seals and gaskets when assembling.
IReplace ATF cooler if excessive foreign material is found in oil
pan or clogging strainer. Refer to ªATF COOLER SERVICEº,
AT-9.
IAfter overhaul, refill the transmission with new ATF.
IWhen the A/T drain plug is removed, only some of the fluid is
drained. Old A/T fluid will remain in torque converter and ATF
cooling system.
Always follow the procedures when changing A/T fluid. Refer
to MA-21, ªChanging A/T Fluidº.
Service Notice or PrecautionsNBAT0004FAIL-SAFENBAT0004S01The TCM has an electronic Fail-Safe (limp home mode). This allows the vehicle to be driven even if a major
electrical input/output device circuit is damaged.
Under Fail-Safe, the vehicle always runs in third gear, even with a shift lever position of ª1º, ª2º or ªDº. The
customer may complain of sluggish or poor acceleration.
When the ignition key is turned ªONº following Fail-Safe operation, O/D OFF indicator lamp blinks for about
8 seconds. (For ªTCM SELF-DIAGNOSTIC PROCEDURE (No Tools)º, refer to AT-46.)
Fail-Safe may occur without electrical circuit damage if the vehicle is driven under extreme conditions (such
as excessive wheel spin followed by sudden braking). To recover normal shift pattern, turn the ignition key
ªOFFº for 5 seconds, then ªONº.
The blinking of the O/D OFF indicator lamp for about 8 seconds will appear only once and be cleared. The
customer may resume normal driving conditions.
Always follow the ªWORK FLOWº (Refer to AT-57).
The SELF-DIAGNOSIS results will be as follows:
The first SELF-DIAGNOSIS will indicate damage to the vehicle speed sensor or the revolution sensor.
During the next SELF-DIAGNOSIS, performed after checking the sensor, no damages will be indicated.
TORQUE CONVERTER SERVICENBAT0004S04The torque converter should be replaced under any of the following conditions:
IExternal leaks in the hub weld area.
IConverter hub is scored or damaged.
IConverter pilot is broken, damaged or fits poorly into crankshaft.
ISteel particles are found after flushing the cooler and cooler lines.
IPump is damaged or steel particles are found in the converter.
IVehicle has TCC shudder and/or no TCC apply. Replace only after all hydraulic and electrical diagnoses
have been made. (Converter clutch material may be glazed.)
IConverter is contaminated with engine coolant containing antifreeze.
IInternal failure of stator roller clutch.
IHeavy clutch debris due to overheating (blue converter).
ISteel particles or clutch lining material found in fluid filter or on magnet when no internal parts in unit are
worn or damaged Ð indicates that lining material came from converter.
The torque converter should not be replaced if:
IThe fluid has an odor, is discolored, and there is no evidence of metal or clutch facing particles.
PRECAUTIONS
Precautions (Cont'd)
AT-8

RemovalNBAT0214
SAT362IA
SAT163K
CAUTION:
When removing the A/T assembly from engine, first remove
the crankshaft position sensor (OBD) from the A/T assembly
lower side.
Be careful not to damage sensor edge.
Ð 4WD MODEL ÐNBAT0214S011. Remove battery negative terminal.
2. Remove exhaust front and rear tubes.
3. Remove fluid charging pipe from A/T assembly.
4. Remove oil cooler pipe from A/T assembly.
5. Plug up openings such as the fluid charging pipe hole, etc.
6. Remove propeller shaft. Refer to PD-4, ªComponentsº.
7. Remove transfer control linkage from transfer. Refer to TF-119,
ªRemovalº.
IInsert plug into rear oil seal after removing rear propeller
shaft.
IBe careful not to damage spline, sleeve yoke and rear oil
seal.
8. Remove A/T control cable from A/T assembly.
9. Disconnect A/T solenoid, PNP switch, turbine revolution, revo-
lution and speedometer sensor harness connectors.
SAT148K
10. Remove starter motor. Refer to SC-18, ªRemoval and Installa-
tionº.
11. Remove bolts securing torque converter to drive plate.
IRemove the bolts by turning crankshaft.
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REMOVAL AND INSTALLATION
Removal
AT-277

SAT017B
IWhen connecting torque converter to transmission, measure
distance ªAº to be certain that they are correctly assembled.
Distance ªAº:
25.0 mm (0.984 in) or more
SAT148K
IInstall converter to drive plate.
IAfter converter is installed to drive plate, rotate crankshaft
several turns and check to be sure that transmission
rotates freely without binding.
SAT149K
ITighten bolts securing transmission.
Bolt No.Tightening torque
N´m (kg-m, ft-lb)Bolt length ªº
mm (in)
1 70 - 80 (7.1 - 8.2, 52 - 59) 65 (2.56)
2 70 - 80 (7.1 - 8.2, 52 - 59) 55 (2.17)
3 29 - 39 (3.0 - 4.0, 22 - 29) 40 (1.57)
IReinstall any part removed.
SAT638A
ICheck fluid level in transmission.
IMove selector lever through all positions to be sure that trans-
mission operates correctly.
With parking brake applied, rotate engine at idling. Move selec-
tor lever through ªNº to ªDº, to ª2º, to ª1º and to ªRº positions.
A slight shock should be felt by hand gripping selector each
time transmission is shifted.
IPerform road test. Refer to ªROAD TESTº, AT-63.
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REMOVAL AND INSTALLATION
Installation (Cont'd)
AT-279

DTC P0217 COOLANT OVERTEMPERATURE
ENRICHMENT PROTECTION.....................................314
On Board Diagnosis Logic.......................................314
Possible Cause ........................................................314
Overall Function Check ...........................................314
Diagnostic Procedure ..............................................316
Main 12 Causes of Overheating..............................319
DTC P0300 - P0306 NO.6-1CYLINDER
MISFIRE, MULTIPLE CYLINDER MISFIRE...............320
On Board Diagnosis Logic.......................................320
Possible Cause ........................................................320
DTC Confirmation Procedure ..................................321
Diagnostic Procedure ..............................................321
DTC P0325 KNOCK SENSOR (KS)...........................328
Component Description ...........................................328
ECM Terminals and Reference Value .....................328
On Board Diagnosis Logic.......................................328
Possible Cause ........................................................328
DTC Confirmation Procedure ..................................328
Wiring Diagram ........................................................330
Diagnostic Procedure ..............................................331
DTC P0335 CRANKSHAFT POSITION SENSOR
(CKPS) (POS)..............................................................334
Component Description ...........................................334
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................334
ECM Terminals and Reference Value .....................335
On Board Diagnosis Logic.......................................335
Possible Cause ........................................................335
DTC Confirmation Procedure ..................................336
Wiring Diagram ........................................................337
Diagnostic Procedure ..............................................338
DTC P0340 CAMSHAFT POSITION SENSOR
(CMPS) (PHASE).........................................................342
Component Description ...........................................342
ECM Terminals and Reference Value .....................342
On Board Diagnosis Logic.......................................342
Possible Cause ........................................................343
DTC Confirmation Procedure ..................................343
Wiring Diagram ........................................................344
Diagnostic Procedure ..............................................345
DTC P0420 (RIGHT BANK, -B1), P0430 (LEFT
BANK, -B2) THREE WAY CATALYST FUNCTION...347
On Board Diagnosis Logic.......................................347
Possible Cause ........................................................347
DTC Confirmation Procedure ..................................348
Overall Function Check ...........................................348
Diagnostic Procedure ..............................................349
DTC P0440 EVAP CONTROL SYSTEM (SMALL
LEAK) (NEGATIVE PRESSURE)................................352
On Board Diagnosis Logic.......................................352
Possible Cause ........................................................352DTC Confirmation Procedure ..................................354
Diagnostic Procedure ..............................................355
DTC P0443 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE (CIRCUIT).................367
Description ...............................................................367
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................367
ECM Terminals and Reference Value .....................368
On Board Diagnosis Logic.......................................368
Possible Cause ........................................................368
DTC Confirmation Procedure ..................................369
Wiring Diagram ........................................................370
Diagnostic Procedure ..............................................371
DTC P0446 EVAPORATIVE EMISSION (EVAP)
CANISTER VENT CONTROL VALVE (CIRCUIT)......374
Component Description ...........................................374
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................374
ECM Terminals and Reference Value .....................374
On Board Diagnosis Logic.......................................374
Possible Cause ........................................................375
DTC Confirmation Procedure ..................................375
Wiring Diagram ........................................................376
Diagnostic Procedure ..............................................377
DTC P0450 EVAPORATIVE EMISSION (EVAP)
CONTROL SYSTEM PRESSURE SENSOR..............381
Component Description ...........................................381
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................381
ECM Terminals and Reference Value .....................381
On Board Diagnosis Logic.......................................382
Possible Cause ........................................................382
DTC Confirmation Procedure ..................................382
Wiring Diagram ........................................................384
Diagnostic Procedure ..............................................385
DTC P0455 EVAP CONTROL SYSTEM (GROSS
LEAK)...........................................................................394
On Board Diagnosis Logic.......................................394
Possible Cause ........................................................394
DTC Confirmation Procedure ..................................396
Diagnostic Procedure ..............................................397
DTC P0460 FUEL LEVEL SENSOR FUNCTION
(SLOSH).......................................................................407
Component Description ...........................................407
On Board Diagnostic Logic......................................407
Possible Cause ........................................................407
DTC Confirmation Procedure ..................................407
Wiring Diagram ........................................................408
Diagnostic Procedure ..............................................409
DTC P0461 FUEL LEVEL SENSOR FUNCTION....... 411
Component Description ........................................... 411
On Board Diagnostic Logic...................................... 411
CONTENTS(Cont'd)
EC-4

Overall Function Check ...........................................492
Diagnostic Procedure ..............................................492
DTC P1165 SWIRL CONTROL VALVE CONTROL
VACUUM CHECK SWITCH.........................................493
Component Description ...........................................493
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................493
ECM Terminals and Reference Value .....................493
On Board Diagnosis Logic.......................................494
Possible Cause ........................................................494
DTC Confirmation Procedure ..................................494
Wiring Diagram ........................................................495
Diagnostic Procedure ..............................................496
DTC P1320 IGNITION SIGNAL...................................499
Component Description ...........................................499
ECM Terminals and Reference Value .....................499
On Board Diagnosis Logic.......................................499
Possible Cause ........................................................500
DTC Confirmation Procedure ..................................500
Wiring Diagram ........................................................501
Diagnostic Procedure ..............................................504
DTC P1335 CRANKSHAFT POSITION SENSOR
(CKPS) (REF)..............................................................510
Component Description ...........................................510
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................510
ECM Terminals and Reference Value .....................510
On Board Diagnosis Logic....................................... 511
Possible Cause ........................................................ 511
DTC Confirmation Procedure .................................. 511
Wiring Diagram ........................................................513
Diagnostic Procedure ..............................................514
DTC P1336 CRANKSHAFT POSITION SENSOR
(CKPS) (POS) (COG)..................................................517
Component Description ...........................................517
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................517
ECM Terminals and Reference Value .....................518
On Board Diagnosis Logic.......................................518
Possible Cause ........................................................518
DTC Confirmation Procedure ..................................519
Wiring Diagram ........................................................520
Diagnostic Procedure ..............................................521
DTC P1441 EVAP CONTROL SYSTEM (VERY
SMALL LEAK).............................................................526
On Board Diagnosis Logic.......................................526
Possible Cause ........................................................526
DTC Confirmation Procedure ..................................527
Diagnostic Procedure ..............................................529
DTC P1444 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE...................................541
Description ...............................................................541CONSULT-II Reference Value in Data Monitor
Mode ........................................................................541
ECM Terminals and Reference Value .....................542
On Board Diagnosis Logic.......................................542
Possible Cause ........................................................542
DTC Confirmation Procedure ..................................543
Wiring Diagram ........................................................544
Diagnostic Procedure ..............................................545
DTC P1446 EVAPORATIVE EMISSION (EVAP)
CANISTER VENT CONTROL VALVE (CLOSE).........553
Component Description ...........................................553
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................553
ECM Terminals and Reference Value .....................553
On Board Diagnosis Logic.......................................553
Possible Cause ........................................................554
DTC Confirmation Procedure ..................................554
Wiring Diagram ........................................................555
Diagnostic Procedure ..............................................556
DTC P1447 EVAPORATIVE EMISSION (EVAP)
CONTROL SYSTEM PURGE FLOW
MONITORING..............................................................561
System Description ..................................................561
On Board Diagnosis Logic.......................................561
Possible Cause ........................................................561
DTC Confirmation Procedure ..................................562
Overall Function Check ...........................................563
Diagnostic Procedure ..............................................564
DTC P1448 EVAPORATIVE EMISSION (EVAP)
CANISTER VENT CONTROL VALVE (OPEN)...........573
Component Description ...........................................573
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................573
ECM Terminals and Reference Value .....................573
On Board Diagnosis Logic.......................................573
Possible Cause ........................................................574
DTC Confirmation Procedure ..................................574
Overall Function Check ...........................................575
Wiring Diagram ........................................................576
Diagnostic Procedure ..............................................577
DTC P1464 FUEL LEVEL SENSOR CIRCUIT
(GROUND SIGNAL)....................................................582
Component Description ...........................................582
On Board Diagnostic Logic......................................582
Possible Cause ........................................................582
DTC Confirmation Procedure ..................................582
Wiring Diagram ........................................................583
Diagnostic Procedure ..............................................584
DTC P1490 VACUUM CUT VALVE BYPASS
VALVE (CIRCUIT)........................................................585
Description ...............................................................585
CONTENTS(Cont'd)
EC-6

CONSULT-II Reference Value in Data Monitor
Mode ........................................................................585
ECM Terminals and Reference Value .....................585
On Board Diagnosis Logic.......................................586
Possible Cause ........................................................586
DTC Confirmation Procedure ..................................586
Wiring Diagram ........................................................587
Diagnostic Procedure ..............................................588
DTC P1491 VACUUM CUT VALVE BYPASS
VALVE..........................................................................591
Description ...............................................................591
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................591
ECM Terminals and Reference Value .....................591
On Board Diagnosis Logic.......................................592
Possible Cause ........................................................592
DTC Confirmation Procedure ..................................592
Overall Function Check ...........................................593
Wiring Diagram ........................................................594
Diagnostic Procedure ..............................................595
DTC P1605 A/T DIAGNOSIS COMMUNICATION
LINE.............................................................................603
Component Description ...........................................603
On Board Diagnosis Logic.......................................603
Possible Cause ........................................................603
DTC Confirmation Procedure ..................................603
DTC P1706 PARK/NEUTRAL POSITION (PNP)
SWITCH.......................................................................604
Component Description ...........................................604
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................604
ECM Terminals and Reference Value .....................604
On Board Diagnosis Logic.......................................604
Possible Cause ........................................................604
DTC Confirmation Procedure ..................................605
Overall Function Check ...........................................606
Wiring Diagram ........................................................607
Diagnostic Procedure ..............................................608
VARIABLE INDUCTION AIR CONTROL SYSTEM
(VIAS)...........................................................................610
Description ...............................................................610
ECM Terminals and Reference Value ..................... 611
Wiring Diagram ........................................................612
Diagnostic Procedure ..............................................613
INJECTOR...................................................................616
Component Description ...........................................616
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................616
ECM Terminals and Reference Value .....................616
Wiring Diagram ........................................................617Diagnostic Procedure ..............................................618
START SIGNAL...........................................................621
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................621
ECM Terminals and Reference Value .....................621
Wiring Diagram ........................................................622
Diagnostic Procedure ..............................................623
FUEL PUMP.................................................................625
System Description ..................................................625
Component Description ...........................................625
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................625
ECM Terminals and Reference Value .....................626
Wiring Diagram ........................................................627
Diagnostic Procedure ..............................................628
POWER STEERING OIL PRESSURE SWITCH.........634
Component Description ...........................................634
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................634
ECM Terminals and Reference Value .....................634
Wiring Diagram ........................................................635
Diagnostic Procedure ..............................................636
REFRIGERANT PRESSURE SENSOR......................639
Description ...............................................................639
ECM Terminals and Reference Value .....................639
Wiring Diagram ........................................................640
Diagnostic Procedure ..............................................641
ELECTRICAL LOAD SIGNAL.....................................643
ECM Terminals and Reference Value .....................643
Wiring Diagram ........................................................644
Diagnostic Procedure ..............................................645
MIL & DATA LINK CONNECTORS............................648
Wiring Diagram ........................................................648
SERVICE DATA AND SPECIFICATIONS (SDS).......649
Fuel Pressure Regulator..........................................649
Idle Speed and Ignition Timing ................................649
Mass Air Flow Sensor..............................................649
Engine Coolant Temperature Sensor ......................649
Heated Oxygen Sensor 1 Heater (Front) ................649
Fuel Pump ...............................................................649
IACV-AAC Valve ......................................................649
Injector .....................................................................649
Resistor ....................................................................649
Throttle Position Sensor ..........................................650
Calculated Load Value.............................................650
Intake Air Temperature Sensor ................................650
Heated Oxygen Sensor 2 Heater (Rear).................650
Crankshaft Position Sensor (REF) ..........................650
Fuel Tank Temperature Sensor ...............................650
Camshaft Position Sensor (PHASE) .......................650GI
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CONTENTS(Cont'd)
EC-7

System ChartNBEC0013
Input (Sensor) ECM Function Output (Actuator)
ICamshaft position sensor (PHASE)
ICrankshaft position sensor (REF)
IMass air flow sensor
IEngine coolant temperature sensor
IHeated oxygen sensor 1 (front)
IIgnition switch
IThrottle position sensor
IClosed throttle position switch*3
IPark/neutral position (PNP) switch
IAir conditioner switch
IKnock sensor
IIntake air temperature sensor
IAbsolute pressure sensor
IEVAP control system pressure sensor*1
IBattery voltage
IPower steering oil pressure switch
IVehicle speed sensor
IFuel tank temperature sensor*1
ICrankshaft position sensor (POS)
IHeated oxygen sensor 2 (rear)*2
ITCM (Transmission control module)
IRefrigerant pressure sensor
IElectrical load
IFuel level sensor*1Fuel injection & mixture ratio control Injectors
Electronic ignition system Power transistor
Idle air control system IACV-AAC valve
Fuel pump control Fuel pump relay
On board diagnostic system MIL (On the instrument panel)
Swirl control valve controlSwirl control valve control solenoid
valve
Power valve control VIAS control solenoid valve
Heated oxygen sensor 1 heater (front) con-
trolHeated oxygen sensor 1 heater
(front)
Heated oxygen sensor 2 heater (rear) controlHeated oxygen sensor 2 heater
(rear)
EVAP canister purge flow controlEVAP canister purge volume con-
trol solenoid valve
Air conditioning cut control Air conditioner relay
ON BOARD DIAGNOSIS for EVAP systemIEVAP canister vent control valve
IVacuum cut valve bypass valve
*1: These sensors are not used to control the engine system. They are used only for the on board diagnosis.
*2: This sensor is not used to control the engine system under normal conditions.
*3: This switch will operate in place of the throttle position sensor to control EVAP parts if the sensor malfunctions.GI
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ENGINE AND EMISSION CONTROL OVERALL SYSTEM
System Chart
EC-27

Multiport Fuel Injection (MFI) System
DESCRIPTIONNBEC0014Input/Output Signal ChartNBEC0014S01
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed (POS signal)
Fuel injec-
tion & mix-
ture ratio
controlInjectors Crankshaft position sensor (REF) Engine speed (REF signal)
Camshaft position sensor (PHASE) Piston position
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Heated oxygen sensor 1 (front) Density of oxygen in exhaust gas
Throttle position sensorThrottle position
Throttle valve idle position
Park/neutral position (PNP) switch Gear position
Vehicle speed sensor Vehicle speed
Ignition switch Start signal
Air conditioner switch Air conditioner operation
Knock sensor Engine knocking condition
Battery Battery voltage
Absolute pressure sensor Ambient air barometric pressure
Power steering oil pressure switch Power steering operation
Heated oxygen sensor 2 (rear)* Density of oxygen in exhaust gas
*: Under normal conditions, this sensor is not for engine control operation.
Basic Multiport Fuel Injection SystemNBEC0014S02The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
Various Fuel Injection Increase/Decrease CompensationNBEC0014S03In addition, the amount of fuel injected is compensated to improve engine performance under various oper-
ating conditions as listed below.

IDuring warm-up
IWhen starting the engine
IDuring acceleration
IHot-engine operation
IWhen selector lever is changed from ªNº to ªDº
IHigh-load, high-speed operation

IDuring deceleration
IDuring high engine speed operation
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTION
Multiport Fuel Injection (MFI) System
EC-28