2001 INFINITI QX4 change time

FOREWORD
This manual contains maintenance and repair procedures for the
2001 INFINITI QX4.
In order to assure your safety and the efficient functioning of the
vehicle, this manual should be read thoroughly. It is especially
important that the PRECAUTIONS in the GI section be completely
understood before starting any repair task.
All information in this manual is based on the latest product infor-
mation at the time of publication. The right is reserved to make
changes in specifications and methods at any time without notice.
IMPORTANT SAFETY NOTICE
The proper performance of service is essential for both the safety of
the technician and the efficient functioning of the vehicle.
The service methods in this Service Manual are described in such a
manner that the service may be performed safely and accurately.
Service varies with the procedures used, the skills of the technician
and the tools and parts available. Accordingly, anyone using service
procedures, tools or parts which are not specifically recommended
by INFINITI must first be completely satisfied that neither personal
safety nor the vehicle's safety will be jeopardized by the service
method selected.

SAT014K
SAT971J
SAT021J
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0039S01CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
TESTING CONDITIONS:
Always drive vehicle on a level road to improve the accuracy of
test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Start engine and select ªDATA MONITORº mode for ªA/Tº with
CONSULT-II.
2) Make sure that output voltage of A/T fluid temperature sensor
is within the range below.
FLUID TEMP SEN: 0.4 - 1.5V
If out of range, drive the vehicle to decrease the voltage (warm
up the fluid) or stop engine to increase the voltage (cool down
the fluid).
3) Select ª1ST GR FNCTN P0731º of ªDTC WORK SUPPORTº
mode for ªA/Tº with CONSULT-II and touch ªSTARTº.
4) Accelerate vehicle to 10 to 20 km/h (6 to 12 MPH) under the
following condition and release the accelerator pedal com-
pletely.
THROTTLE POSI: Less than 1.0/8 (at all times during step
4)
Selector lever: D position (OD ªONº)
ICheck that ªGEARº shows ª2º after releasing pedal.
5) Depress accelerator pedal to WOT (more than 7.0/8 of
ªTHROTTLE POSIº) quickly from a speed of 10 to 20 km/h (6
to 12 MPH) until ªTESTINGº changes to ªSTOP VEHICLEº or
ªCOMPLETEDº. (It will take approximately 3 seconds.)
If the check result NG appears on CONSULT-II screen, go to
ªDIAGNOSTIC PROCEDUREº, AT-124.
If ªSTOP VEHICLEº appears on CONSULT-II screen, go to the
following step.
ICheck that ªGEARº shows ª1º when depressing accelera-
tor pedal to WOT.
IIf ªTESTINGº does not appear on CONSULT-II for a long
time, select ªSELF-DIAG RESULTSº for ªENGINEº. In case
a 1st trip DTC other than P0731 is shown, refer to appli-
cable ªTROUBLE DIAGNOSIS FOR DTCº.
6) Stop vehicle.
7) Follow the instruction displayed. (Check for normal shifting
referring to the table below.)
Vehicle conditionGear on actual transmission shift pattern when
screen is changed to 1,2,3,4
No malfunction exists 1,2,3,4
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DTC P0731 IMPROPER SHIFTING TO 1ST GEAR POSITION
Description (Cont'd)
AT-121

SAT014K
SAT971J
SAT021J
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0042S01CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
TESTING CONDITIONS:
Always drive vehicle on a level road to improve the accuracy
of test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Start engine and select ªDATA MONITORº mode for ªA/Tº with
CONSULT-II.
2) Make sure that output voltage of A/T fluid temperature sensor
is within the range below.
FLUID TEMP SEN: 0.4 - 1.5V
If out of range, drive the vehicle to decrease the voltage (warm
up the fluid) or stop engine to increase the voltage (cool down
the fluid).
3) Select ª2ND GR FNCTN P0732º of ªDTC WORK SUPPORTº
mode for ªA/Tº with CONSULT-II and touch ªSTARTº.
4) Accelerate vehicle to 25 to 30 km/h (16 to 19 MPH) under the
following condition and release the accelerator pedal com-
pletely.
THROTTLE POSI: Less than 1.0/8 (at all times during step
4)
Selector lever: D position (OD ªONº)
ICheck that ªGEARº shows ª3º or ª4º after releasing pedal.
5) Depress accelerator pedal to WOT (more than 7.0/8 of
ªTHROTTLE POSIº) quickly from a speed of 25 to 30 km/h (16
to 19 MPH) until ªTESTINGº changes to ªSTOP VEHICLEº or
ªCOMPLETEDº. (It will take approximately 3 seconds.)
If the check result NG appears on CONSULT-II screen, go to
ªDIAGNOSTIC PROCEDUREº, AT-130.
If ªSTOP VEHICLEº appears on CONSULT-II screen, go to
following step.
ICheck that ªGEARº shows ª2º when depressing accelera-
tor pedal to WOT.
IIf ªTESTINGº does not appear on CONSULT-II for a long
time, select ªSELF-DIAG RESULTSº for ªENGINEº. In case
a 1st trip DTC other than P0732 is shown, refer to appli-
cable ªTROUBLE DIAGNOSIS FOR DTCº.
6) Stop vehicle.
7) Follow the instruction displayed. (Check for normal shifting
referring to the table below.)
Vehicle conditionGear on actual transmission shift pattern when
screen is changed to 1,2,3,4
No malfunction exists 1,2,3,4
Malfunction for P0732 exists. 4,3,3,4
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DTC P0732 IMPROPER SHIFTING TO 2ND GEAR POSITION
Description (Cont'd)
AT-127

SAT014K
SAT971J
SAT021J
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0045S01CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
TESTING CONDITIONS:
Always drive vehicle on a level road to improve the accuracy
of test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Start engine and select ªDATA MONITORº mode for ªA/Tº with
CONSULT-II.
2) Make sure that output voltage of A/T fluid temperature sensor
is within the range below.
FLUID TEMP SEN: 0.4 - 1.5V
If out of range, drive the vehicle to decrease the voltage (warm
up the fluid) or stop engine to increase the voltage (cool down
the fluid).
3) Select ª3RD GR FNCTN P0733º of ªDTC WORK SUPPORTº
mode for ªA/Tº with CONSULT-II and touch ªSTARTº.
4) Accelerate vehicle to 35 to 45 km/h (22 to 28 MPH) under the
following condition and release the accelerator pedal com-
pletely.
THROTTLE POSI: Less than 1.0/8 (at all times during step
4)
Selector lever: D position (OD ªONº)
ICheck that ªGEARº shows ª4º after releasing pedal.
5) Depress accelerator pedal steadily with 3.5/8 - 4.5/8 of
ªTHROTTLE POSIº from a speed of 35 to 45 km/h (22 to 28
MPH) until ªTESTINGº changes to ªSTOP VEHICLEº or ªCOM-
PLETEDº. (It will take approximately 3 seconds.)
If the check result NG appears on CONSULT-II screen, go to
ªDIAGNOSTIC PROCEDUREº, AT-136.
If ªSTOP VEHICLEº appears on CONSULT-II screen, go to
following step.
ICheck that ªGEARº shows ª3º when depressing accelera-
tor pedal with 3.5/8 - 4.5/8 of ªTHROTTLE POSIº.
IIf ªTESTINGº does not appear on CONSULT-II for a long
time, select ªSELF-DIAG RESULTSº for ªENGINEº. In case
a 1st trip DTC other than P0733 is shown, refer to appli-
cable ªTROUBLE DIAGNOSIS FOR DTCº.
6) Stop vehicle.
7) Follow the instruction displayed. (Check for normal shifting
referring to the table below.)
Vehicle conditionGear on actual transmission shift pattern
when screen is changed to 1,2,3,4
No malfunction exists. 1,2,3,4
Malfunction for P0733 exists. 1,1,4,4
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DTC P0733 IMPROPER SHIFTING TO 3RD GEAR POSITION
Description (Cont'd)
AT-133

SAT014K
SAT971J
SAT021J
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0048S01CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
TESTING CONDITIONS:
Always drive vehicle on a level road to improve the accuracy
of test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Start engine and select ªDATA MONITORº mode for ªA/Tº with
CONSULT-II.
2) Make sure that output voltage of A/T fluid temperature sensor
is within the range below.
FLUID TEMP SEN: 0.4 - 1.5V
If out of range, drive the vehicle to decrease the voltage (warm
up the fluid) or stop engine to increase the voltage (cool down
the fluid).
3) Select ª4TH GR FNCTN P0734º of ªDTC WORK SUPPORTº
mode for ªA/Tº with CONSULT-II and touch ªSTARTº.
4) Accelerate vehicle to 55 to 65 km/h (34 to 40 MPH) under the
following condition and release the accelerator pedal com-
pletely.
THROTTLE POSI: Less than 5.5/8 (at all times during step
4)
Selector lever: D position (OD ªONº)
ICheck that ªGEARº shows ª3º after releasing pedal.
5) Depress accelerator pedal steadily with 1.0/8 - 2.0/8 of
ªTHROTTLE POSIº from a speed of 55 to 65 km/h (34 to 40
MPH) until ªTESTINGº has turned to ªSTOP VEHICLEº or
ªCOMPLETEDº. (It will take approximately 3 seconds.)
If the check result NG appears on CONSULT-II screen, go to
ªDIAGNOSTIC PROCEDUREº, AT-143.
If ªSTOP VEHICLEº appears on CONSULT-II screen, go to
following step.
ICheck that ªGEARº shows ª4º when depressing accelera-
tor pedal with 1.0/8 - 2.0/8 of ªTHROTTLE POSIº.
IIf ªTESTINGº does not appear on CONSULT-II for a long
time, select ªSELF-DIAG RESULTSº for ªENGINEº. In case
a 1st trip DTC other than P0734 is shown, refer to appli-
cable ªTROUBLE DIAGNOSIS FOR DTCº.
6) Stop vehicle.
7) Follow the instruction displayed. (Check for normal shifting
referring to the table below.)
Vehicle conditionGear on actual transmission shift pattern when
screen is changed to 1,2,3,4
No malfunction exists 1,2,3,4
Malfunction for P0734 exists. 1,2,2,1
DTC P0734 IMPROPER SHIFTING TO 4TH GEAR POSITION
Description (Cont'd)
AT-140

SBR002A
SBR365AA
On-vehicle ServiceNBBR0024OPERATING CHECKNBBR0024S011. Depress brake pedal several times with engine off. After
exhausting vacuum, make sure there is no change in pedal
stroke.
2. Depress brake pedal, then start engine. If pedal goes down
slightly, operation is normal.
AIRTIGHT CHECKNBBR0024S021. Start engine, and stop it after one or two minutes. Depress
brake pedal several times slowly. Booster is airtight if pedal
stroke is less each time.
2. Depress brake pedal while engine is running, and stop engine
with pedal depressed. The pedal stroke should not change
after holding pedal down for30 seconds.
SBR368DA
RemovalNBBR0025CAUTION:
IBe careful not to splash brake fluid on painted areas; it
may cause paint damage. If brake fluid is splashed on
painted areas, wash it away with water immediately.
IBe careful not to deform or bend brake pipes, during
removal of booster.
SBR208E
InspectionNBBR0026OUTPUT ROD LENGTH CHECKNBBR0026S011. Apply vacuum of þ66.7 kPa (þ500 mmHg, þ19.69 inHg) to
brake booster with a hand vacuum pump.
2. Add preload of 19.6 N (2.0 kg, 4.4 lb) to output rod.
3. Check output rod length.
Specified length:
10.275 - 10.525 mm (0.4045 - 0.4144 in)
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BRAKE BOOSTER
On-vehicle Service
BR-19

TRUNK=NBBT0025S04Trunk noises are often caused by a loose jack or loose items put into the trunk by the owner.
In addition look for:
1. Trunk lid bumpers out of adjustment
2. Trunk lid striker out of adjustment
3. The trunk lid torsion bars knocking together
4. A loose license plate or bracket
Most of these incidents can be repaired by adjusting, securing or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINERNBBT0025S05Noises in the sunroof/headliner area can often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knocking noise
2. Sunvisor shaft shaking in the holder
3. Front or rear windshield touching headliner and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
SEATSNBBT0025S06When isolating seat noises it's important to note the position the seat is in and the load placed on the seat
when the noise is present. These conditions should be duplicated when verifying and isolating the cause of
the noise.
Cause of seat noise include:
1. Headrest rods and holders
2. A squeak between the seat pad cushion and frame
3. The rear seat back lock and bracket
These noises can be isolated by moving or pressing on the suspected components while duplicating the con-
ditions under which the noise occurs. Most of these incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOODNBBT0025S07Some interior noises may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noises include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move or insulate one component at a time and test drive the vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
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SQUEAK AND RATTLE TROUBLE DIAGNOSES
Generic Squeak and Rattle Troubleshooting (Cont'd)
BT-7

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