2001 INFINITI QX4 check engine

2 CHECK SYMPTOM
1. Apply brake.
2. Start engine.
Does the symptom appear only when engine is started?
Ye s©Carry out self-diagnosis. Refer to BR-41, 44.
No©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-70.
NOTE:
ABS may operate and cause vibration under any of the following
conditions.
IApplying brake gradually when shifting or operating clutch.
ILow friction (slippery) road.
IHigh speed cornering.
IDriving over bumps and pot holes.
IEngine speed is over 5,000 rpm with vehicle stopped.
6. Warning Lamp Does Not Come On When
Ignition Switch Is Turned On
NBBR0112
1 INSPECTION START
Warning lamp circuit inspection
SBR673E
©GO TO 2.
2 CHECK FUSE
Check 10A fuse No. 8. For fuse layout, refer to EL-16, ªPOWER SUPPLY ROUTINGº.
Is fuse OK?
Ye s©GO TO 3.
No©Replace fuse.
TROUBLE DIAGNOSES FOR SYMPTOMSABS
5. Pedal Vibration and Noise (Cont'd)
BR-72

BODY & TRIM
SECTION
BT
CONTENTS
PRECAUTIONS...............................................................2
Service Notice..............................................................2
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............2
PREPARATION...............................................................3
Special Service Tools ..................................................3
Commercial Service Tools ...........................................3
SQUEAK AND RATTLE TROUBLE DIAGNOSES.........4
Work Flow ....................................................................4
CUSTOMER INTERVIEW...........................................4
DUPLICATE THE NOISE AND TEST DRIVE................5
CHECK RELATED SERVICE BULLETINS...................5
LOCATE THE NOISE AND IDENTIFY THE ROOT
CAUSE
.....................................................................5
REPAIR THE CAUSE.................................................5
CONFIRM THE REPAIR.............................................6
Generic Squeak and Rattle Troubleshooting ..............6
INSTRUMENT PANEL................................................6
CENTER CONSOLE..................................................6
DOORS.....................................................................6
TRUNK.....................................................................7
SUNROOF/HEADLINER.............................................7
SEATS......................................................................7
UNDERHOOD...........................................................7
Diagnostic Worksheet ..................................................8
CLIP AND FASTENER..................................................10
Description .................................................................10
BODY FRONT END.......................................................12
Removal and Installation ...........................................12
FRONT BUMPER ASSEMBLY..................................12
BODY REAR END AND OPENER................................15
Removal and Installation ...........................................15
REAR BUMPER ASSEMBLY....................................15
FRONT DOOR...............................................................18
Overhaul ....................................................................18
Front Door Limit Switch Reset ..................................19
RESET CONDITIONS..............................................19
RESET PROCEDURES............................................19
REAR DOOR.................................................................20
Overhaul ....................................................................20INSTRUMENT PANEL ASSEMBLY.............................21
Removal and Installation ...........................................21
SIDE AND FLOOR TRIM...............................................28
Removal and Installation ...........................................28
DOOR TRIM...................................................................30
Removal and Installation ...........................................30
ROOF TRIM...................................................................32
Removal and Installation ...........................................32
BACK DOOR TRIM.......................................................34
Removal and Installation ...........................................34
EXTERIOR.....................................................................35
Removal and Installation ...........................................35
FRONT SEAT................................................................41
Removal and Installation ...........................................41
HEATED SEAT........................................................43
REAR SEAT...................................................................44
Removal and Installation ...........................................44
SUNROOF......................................................................45
Adjustment .................................................................45
Removal and Installation ...........................................45
Trouble Diagnoses.....................................................49
DIAGNOSTIC TABLE................................................49
WIND DEFLECTOR.................................................49
ADJUSTMENT.........................................................50
DRAIN HOSES........................................................51
WEATHERSTRIP.....................................................51
LINK AND WIRE ASSEMBLY....................................52
WINDSHIELD AND WINDOWS....................................53
Removal and Installation ...........................................53
REMOVAL...............................................................53
INSTALLATION........................................................53
WINDSHIELD..........................................................54
REAR SIDE WINDOW..............................................55
DOOR MIRROR.............................................................56
Removal and Installation ...........................................56
BODY (ALIGNMENT)....................................................57
Alignment ...................................................................57
ENGINE COMPARTMENT........................................58
UNDERBODY..........................................................60
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DUPLICATE THE NOISE AND TEST DRIVENBBT0024S02If possible, drive the vehicle with the customer until the noise is duplicated. Note any additional information on
the Diagnostic Worksheet regarding the conditions or location of the noise. This information can be used to
duplicate the same conditions when you confirm the repair.
If the noise can be duplicated easily during the test drive, to help identify the source of the noise, try to dupli-
cate the noise with the vehicle stopped by doing one or all of the following:
1) Close a door.
2) Tap or push/pull around the area where the noise appears to be coming from.
3) Rev the engine.
4) Use a floor jack to recreate vehicle ªtwistº.
5) At idle, apply engine load (electrical load, half-clutch on M/T model, drive position on A/T model).
6) Raise the vehicle on a hoist and hit a tire with a rubber hammer.
IDrive the vehicle and attempt to duplicate the conditions the customer states exist when the noise occurs.
IIf it is difficult to duplicate the noise, drive the vehicle slowly on an undulating or rough road to stress the
vehicle body.
CHECK RELATED SERVICE BULLETINSNBBT0024S03After verifying the customer concern or symptom, check ASIST for Technical Service Bulletins (TSBs) related
to that concern or symptom.
If a TSB relates to the symptom, follow the procedure to repair the noise.
LOCATE THE NOISE AND IDENTIFY THE ROOT CAUSENBBT0024S041. Narrow down the noise to a general area. To help pinpoint the source of the noise, use a listening tool
(Chassis Ear: J-39570, Engine Ear: J-39565 and mechanics stethoscope).
2. Narrow down the noise to a more specific area and identify the cause of the noise by:
Iremoving the components in the area that you suspect the noise is coming from.
Do not use too much force when removing clips and fasteners, otherwise clips and fastener can
be broken or lost during the repair, resulting in the creation of new noise.
Itapping or pushing/pulling the component that you suspect is causing the noise.
Do not tap or push/pull the component with excessive force, otherwise the noise will be eliminated
only temporarily.
Ifeeling for a vibration with your hand by touching the component(s) that you suspect is (are) causing the
noise.
Iplacing a piece of paper between components that you suspect are causing the noise.
Ilooking for loose components and contact marks.
Refer to ªGeneric Squeak and Rattle Troubleshootingº, BT-6.
REPAIR THE CAUSENBBT0024S05IIf the cause is a loose component, tighten the component securely.
IIf the cause is insufficient clearance between components:
þ separate components by repositioning or loosening and retightening the component, if possible.
þ insulate components with a suitable insulator such as urethane pads, foam blocks, felt cloth tape or ure-
thane tape. A Nissan Squeak and Rattle Kit (J-43980) is available through your authorized Nissan Parts
Department.
CAUTION:
Do not use excessive force as many components are constructed of plastic and may be damaged.
Always check with the Parts Department for the latest parts information.
The following materials are contained in the Nissan Squeak and Rattle Kit (J-43980). Each item can be ordered
separately as needed.
URETHANE PADS [1.5 mm (0.059 in) thick]
Insulates connectors, harness, etc.
76268-9E005: 100 x 135 mm (3.94 x 5.31 in)/76884-71L01: 60 x 85 mm (2.36 x 3.35 in)/76884-71L02: 15 x
25 mm (0.59 x 0.98 in)
INSULATOR (Foam blocks)
Insulates components from contact. Can be used to fill space behind a panel.
73982-9E000: 45 mm (1.77 in) thick, 50 x 50 mm (1.97 x 1.97 in)/73982-50Y00: 10 mm (0.39 in) thick, 50 x
50 mm (1.97 x 1.97 in)
INSULATOR (Light foam block)
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SQUEAK AND RATTLE TROUBLE DIAGNOSES
Work Flow (Cont'd)
BT-5

ENGINE CONTROL SYSTEM
SECTION
EC
CONTENTS
TROUBLE DIAGNOSIS - INDEX....................................8
Alphabetical & P No. Index for DTC ...........................8
PRECAUTIONS.............................................................14
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER².............14
Precautions for On Board Diagnostic (OBD)
System of Engine and A/T.........................................14
Engine Fuel & Emission Control System ..................15
Precautions ................................................................16
Wiring Diagrams and Trouble Diagnosis ...................17
PREPARATION.............................................................18
Special Service Tools ................................................18
Commercial Service Tools .........................................18
ENGINE AND EMISSION CONTROL OVERALL
SYSTEM.........................................................................20
Engine Control Component Parts Location ...............20
Circuit Diagram ..........................................................24
System Diagram ........................................................25
Vacuum Hose Drawing ..............................................26
System Chart .............................................................27
ENGINE AND EMISSION BASIC CONTROL
SYSTEM DESCRIPTION...............................................28
Multiport Fuel Injection (MFI) System .......................28
Electronic Ignition (EI) System ..................................30
Air Conditioning Cut Control ......................................31
Fuel Cut Control (at no load & high engine
speed) ........................................................................32
Evaporative Emission System ...................................32
Positive Crankcase Ventilation ..................................38
BASIC SERVICE PROCEDURE...................................39
Fuel Pressure Release ..............................................39
Fuel Pressure Check .................................................39
Fuel Pressure Regulator Check ................................40
Injector .......................................................................41
How to Check Idle Speed and Ignition Timing ..........42
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment .................................................................43
Idle Air Volume Learning ...........................................57ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION...............................................................59
Introduction ................................................................59
Two Trip Detection Logic ...........................................59
Emission-related Diagnostic Information ...................60
Malfunction Indicator Lamp (MIL) ..............................74
OBD System Operation Chart ...................................75
CONSULT-II ...............................................................81
Generic Scan Tool (GST) ..........................................95
TROUBLE DIAGNOSIS - INTRODUCTION..................97
Introduction ................................................................97
Work Flow ..................................................................99
TROUBLE DIAGNOSIS - BASIC INSPECTION.........101
Basic Inspection.......................................................101
TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION............................................................. 116
DTC Inspection Priority Chart.................................. 116
Fail-safe Chart ......................................................... 117
Symptom Matrix Chart ............................................. 118
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................122
Major Sensor Reference Graph in Data Monitor
Mode ........................................................................124
ECM Terminals and Reference Value .....................127
TROUBLE DIAGNOSIS - SPECIFICATION VALUE..136
Description ...............................................................136
Testing Condition .....................................................136
Inspection Procedure ...............................................136
Diagnostic Procedure ..............................................137
TROUBLE DIAGNOSIS FOR INTERMITTENT
INCIDENT.....................................................................140
Description ...............................................................140
Diagnostic Procedure ..............................................140
TROUBLE DIAGNOSIS FOR POWER SUPPLY........141
ECM Terminals and Reference Value .....................141
Main Power Supply and Ground Circuit ..................142
DTC P0100 MASS AIR FLOW SENSOR (MAFS)......150
Component Description ...........................................150
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CONSULT-II Reference Value in Data Monitor
Mode ........................................................................150
ECM Terminals and Reference Value .....................150
On Board Diagnosis Logic.......................................151
Possible Cause ........................................................151
DTC Confirmation Procedure ..................................151
Overall Function Check ...........................................153
Wiring Diagram ........................................................154
Diagnostic Procedure ..............................................155
DTC P0105 ABSOLUTE PRESSURE SENSOR........158
Component Description ...........................................158
ECM Terminals and Reference Value .....................158
On Board Diagnosis Logic.......................................158
Possible Cause ........................................................159
DTC Confirmation Procedure ..................................159
Wiring Diagram ........................................................160
Diagnostic Procedure ..............................................161
DTC P0110 INTAKE AIR TEMPERATURE
SENSOR......................................................................164
Component Description ...........................................164
On Board Diagnosis Logic.......................................164
Possible Cause ........................................................164
DTC Confirmation Procedure ..................................164
Wiring Diagram ........................................................166
Diagnostic Procedure ..............................................167
DTC P0115 ENGINE COOLANT TEMPERATURE
SENSOR (ECTS) (CIRCUIT).......................................169
Component Description ...........................................169
On Board Diagnosis Logic.......................................169
Possible Cause ........................................................170
DTC Confirmation Procedure ..................................170
Wiring Diagram ........................................................171
Diagnostic Procedure ..............................................172
DTC P0120 THROTTLE POSITION SENSOR...........174
Description ...............................................................174
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................174
ECM Terminals and Reference Value .....................175
On Board Diagnosis Logic.......................................175
Possible Cause ........................................................175
DTC Confirmation Procedure ..................................176
Wiring Diagram ........................................................180
Diagnostic Procedure ..............................................181
DTC P0125 ENGINE COOLANT TEMPERATURE
SENSOR (ECTS).........................................................187
Description ...............................................................187
On Board Diagnosis Logic.......................................187
Possible Cause ........................................................188
DTC Confirmation Procedure ..................................188
Wiring Diagram ........................................................189
Diagnostic Procedure ..............................................190DTC P0130, P0150 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (CIRCUIT)..................192
Component Description ...........................................192
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................192
ECM Terminals and Reference Value .....................192
On Board Diagnosis Logic.......................................193
Possible Cause ........................................................193
DTC Confirmation Procedure ..................................194
Overall Function Check ...........................................194
Wiring Diagram ........................................................196
Diagnostic Procedure ..............................................198
DTC P0131, P0151 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (LEAN SHIFT
MONITORING).............................................................202
Component Description ...........................................202
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................202
ECM Terminals and Reference Value .....................202
On Board Diagnosis Logic.......................................203
Possible Cause ........................................................203
DTC Confirmation Procedure ..................................203
Overall Function Check ...........................................204
Diagnostic Procedure ..............................................205
DTC P0132, P0152 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (RICH SHIFT
MONITORING).............................................................210
Component Description ...........................................210
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................210
ECM Terminals and Reference Value .....................210
On Board Diagnosis Logic....................................... 211
Possible Cause ........................................................ 211
DTC Confirmation Procedure .................................. 211
Overall Function Check ...........................................212
Diagnostic Procedure ..............................................213
DTC P0133, P0153 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (RESPONSE
MONITORING).............................................................218
Component Description ...........................................218
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................218
ECM Terminals and Reference Value .....................218
On Board Diagnosis Logic.......................................219
Possible Cause ........................................................219
DTC Confirmation Procedure ..................................220
Overall Function Check ...........................................221
Wiring Diagram ........................................................222
Diagnostic Procedure ..............................................224
DTC P0134, P0154 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (HIGH VOLTAGE)......231
Component Description ...........................................231
CONTENTS(Cont'd)
EC-2

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

operates, the flow rate of vapor controlled by EVAP canister purge volume control solenoid valve is propor-
tionally regulated as the air flow increases.
EVAP canister purge volume control solenoid valve also shuts off the vapor purge line during decelerating and
idling.
SEF428T
INSPECTIONNBEC0019EVAP CanisterNBEC0019S01Check EVAP canister as follows:
1. Pinch the fresh air hose.
2. Blow air into portAand check that it flows freely out of portB.
SEF231SB
Tightening TorqueNBEC0019S02Tighten EVAP canister as shown in the figure.
Make sure new O-ring is installed properly between EVAP can-
ister and EVAP canister vent control valve.
SEF427N
SEF943S
Fuel Tank Vacuum Relief Valve (Built into fuel filler cap)NBEC0019S031. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.
Pressure:
15.3 - 20.0 kPa (0.156 - 0.204 kg/cm
2, 2.22 - 2.90 psi)
Vacuum:
þ6.0 to þ3.3 kPa (þ0.061 to þ0.034 kg/cm
2, þ0.87 to
þ0.48 psi)
3. If out of specification, replace fuel filler cap as an assembly.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incor-
rect fuel filler cap is used, the MIL may come on.
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ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTION
Evaporative Emission System (Cont'd)
EC-33

SEF372Q
SEF559A
Positive Crankcase Ventilation
DESCRIPTIONNBEC0021This system returns blow-by gas to the intake manifold.
The positive crankcase ventilation (PCV) valve is provided to con-
duct crankcase blow-by gas to the intake manifold.
During partial throttle operation of the engine, the intake manifold
sucks the blow-by gas through the PCV valve.
Normally, the capacity of the valve is sufficient to handle any
blow-by and a small amount of ventilating air.
The ventilating air is then drawn from the air inlet tubes into the
crankcase. In this process the air passes through the hose con-
necting air inlet tubes to rocker cover.
Under full-throttle condition, the manifold vacuum is insufficient to
draw the blow-by flow through the valve. The flow goes through the
hose connection in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not
meet the requirement. This is because some of the flow will go
through the hose connection to the air inlet tubes under all
conditions.
SEC137A
INSPECTIONNBEC0022PCV (Positive Crankcase Ventilation) ValveNBEC0022S01With engine running at idle, remove PCV valve ventilation hose
from PCV valve; if the valve is working properly, a hissing noise will
be heard as air passes through it and a strong vacuum should be
felt immediately when a finger is placed over valve inlet.
ET277
PCV Valve Ventilation HoseNBEC0022S021. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any
hose cannot be freed of obstructions, replace.
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTION
Positive Crankcase Ventilation
EC-38