2001 INFINITI QX4 Fuel

ACCELERATOR CONTROL, FUEL &
EXHAUST SYSTEMS
SECTION
FE
CONTENTS
PREPARATION...............................................................2
Special Service Tool ....................................................2
Commercial Service Tools ...........................................2
ACCELERATOR CONTROL SYSTEM...........................3
Removal and Installation .............................................3
Adjusting Accelerator Wire ..........................................3FUEL SYSTEM................................................................4
Removal and Installation .............................................4
FUEL TANK...............................................................5
FUEL PUMP AND GAUGE.........................................6
EXHAUST SYSTEM........................................................8
Removal and Installation .............................................8
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Removal and InstallationNBFE0004WARNING:
When replacing fuel line parts, be sure to observe the follow-
ing:
IPut a ªCAUTION: INFLAMMABLEº sign in workshop.
IDo not smoke while servicing fuel system. Keep open
flames and sparks away from work area.
IBe sure to furnish the workshop with a CO
2fire extin-
guisher.
CAUTION:
IBefore removing fuel line parts, carry out the following
procedures:
a) Put drained fuel in an explosion-proof container and put
lid on securely.
b) Release fuel pressure from fuel line. Refer to MA-16,
ªChanging Fuel Filterº.
c) Disconnect battery ground cable.
IAlways replace O-ring with new ones.
IDo not kink or twist hose and tube when they are installed.
IDo not tighten hose clamps excessively to avoid damag-
ing hoses.
IWhen installing fuel check valve, be careful of its desig-
nated direction. Refer to EC-32, ªEVAPORATIVE EMIS-
SION SYSTEMº.
IAfter installation, run engine and check for fuel leaks at
connections.
FUEL SYSTEM
Removal and Installation
FE-4

SFE419AA
SFE420A
FUEL TANKNBFE0004S011. Release fuel pressure from fuel line.
Refer to MA-16, ªChanging Fuel Filterº.
2. Remove inspection hole cover located behind the rear seat.
3. Disconnect harness connectors under inspection hole cover.
4. Disconnect fuel hoses.
IPut mating marks on hoses for correct installation.
SFE468A
5. Disconnect filler hose, vent hose and evaporation hose at fuel
tank side.
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FUEL SYSTEM
Removal and Installation (Cont'd)
FE-5

SFE422A
6. Remove parking brake wire from fuel tank protector.
7. Remove fuel tank protector.
SFE469A
8. Remove fuel tank band mounting bolts while supporting fuel
tank.
9. Remove fuel tank.
Installation procedure is the reverse order of removal.
FUEL PUMP AND GAUGENBFE0004S02
SFE541A
1. Release fuel pressure from fuel line.
Refer to MA-16, ªChanging Fuel Filterº.
2. Remove inspection hole cover located behind the rear seat.
3. Disconnect harness connectors and fuel tubes from upper
plate of fuel gauge.
IPut mating marks on tubes for correct installation.
4. Remove fuel gauge retainer and fuel gauge.
FUEL SYSTEM
Removal and Installation (Cont'd)
FE-6

SFE544A
5. Disconnect the quick connectors as follows.
1) Put mating marks on tubes and connectors for correct instal-
lation.
2) Hold the sides of the connector, push in tabs, and pull out the
tube inserted in the retainer.
CAUTION:
IThe tube can be removed when the push in tabs are com-
pletely depressed. Do not twist it more than necessary.
IDo not use any tools to remove the quick connector.
IKeep the connecting portion of the tubes and quick con-
nectors clean.
SFE425A
6. Remove fuel pump with bracket while lifting the pawl of the fuel
pump bracket upward.
AFE113
7. To install, reverse the removal procedure. Connect the quick
connectors as follows.
IBe sure that the connecting portion is clean and smooth.
IAlign mating marks.
IInsert tube into the center of the connector until you hear a
click.
AFE114
After connecting quick connectors, make sure the connection is
firmly made using the following method.
IPull on the fuel tube and connector to make sure they are firmly
connected.
IStart the engine, increase engine speed and verify that there
are no leaks.
SFE428A
IInstall fuel gauge as shown.
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FUEL SYSTEM
Removal and Installation (Cont'd)
FE-7

QUICK REFERENCE CHART: QX42001
Engine model VQ35DE
Firing order 1-2-3-4-5-6
Idle speed rpmA/T
(in ªNº position)750 50
Ignition timing (degree BTDC at idle speed) 15É 2É
CO% at idleIdle mixture screw is preset and
sealed at factory.
Drive belt deflection (Cold) mm (in) Used belt
Deflection of
new belt
LimitDeflection
after
adjustment
Alternator
Power steering oil pump
Fan7 (0.28)4-5
(0.16 - 0.20)3.5 - 4.5
(0.138 - 0.177)
Air conditioner compressor 12 (0.472)9-10
(0.354 - 0.394)8-9
(0.31 - 0.35)
Applied pressed force
N (kg, lb)98 (10, 22)
Drive belt tension adjustment (Cold)
N (kg, lb)Used belt
New belt
LimitAfter
adjustment
Alternator
Power steering pump
Fan294 (30, 66)730 - 818
(74.4 - 83.5,
164 - 184)838 - 926
(85.4 - 94.5,
188 - 208)
Air conditioner compressor 196 (20, 44)348 - 436
(35.5 - 44.5,
78 - 98)470 - 559
(47.9 - 57.0,
106 - 126)
Radiator cap relief pressure
kPa (kg/cm
2, psi)78 - 98 (0.8 - 1.0, 11 - 14)
Cooling system leakage testing pressure
kPa (kg/cm
2, psi)157 (1.6, 23)
Compression pressure
kPa (kg/cm
2, psi)/rpmStandard 1,275 (13.0, 185)/300
Minimum 981 (10.0, 142)/300
Spark plugStandard PLFR5A-11
Cold PLFR6A-11
Hot PLFR4A-11
Applied model 245/70 R16 tire
Camber
Degree minute
(Decimal degree)Minimum þ0É35¢(þ0.58É)
Nominal 0É10¢(0.17É)
Maximum 0É55¢(0.92É)
Left and right
difference45¢(0.75É) or less
Caster
Degree minute
(Decimal degree)Minimum 2É15¢(2.25É)
Nominal 3É00¢(3.00É)
Maximum 3É45¢(3.75É)
Left and right
difference45¢(0.75É) or less
Total toe-in Minimum 1 (0.04)
Distance (A þ B)
mm (in)Nominal 2 (0.08)
Maximum 3 (0.12)
Angle (left plus right)
Degree minute
(Decimal degree)Minimum 5¢(0.08É)
Nominal 10¢(0.17É)
Maximum 15¢(0.25É)
Wheel turning angle
(Full turn)Minimum 30É00¢(30.00É)
Inside
Degree minute
(Decimal degree)Nominal 33É00¢(33.00É)
Maximum 34É00¢(34.00É)
Outside
Degree minute
(Decimal degree)Minimum 28É00¢(28.00É)
Nominal 31É00¢(31.00É)
Maximum 32É00¢(32.00É)
* Fuel, radiator coolant and engine oil full.
Spare tire, jack, hand tools and mats in designated positions.
Unit: mm (in)Front brake
Pad wear limit 2.0 (0.079)
Rotor repair limit 26.0 (1.024)
Rear brake
Lining wear limit 1.5 (0.059)
Drum repair limit 296.5 (11.67)
Pedal free height 175 - 185 (6.89 - 7.28)
Pedal depressed height*1 70 (2.76)
Parking brake
Number of notches*2 6 - 8
*1 Under force of 490 N (50 kg, 110 lb) with engine running
*2 At pulling force: 196 N (20 kg, 44 lb)
Unit Liter US measure
Coolant with reservoir 9.2 9-3/4 qt
Engine*With oil filter 5.0 5-1/4 qt
Without oil filter 4.8 5-1/8 qt
Dry engine (engine overhaul) 6.8 7-1/4 qt
Transmis-
sionA/T2WD
8.5 9 qt
4WD
All-mode 4WD transfer 3.0 2-5/8 qt
Differential carrierFront 1.85 3-7/8 pt
Rear 2.8 5-7/8 pt
Power steering system 0.9 1 qt
Air conditioning systemRefrigerant 0.60 - 0.70 kg 1.32 - 1.54 lb
Compressor
oil0.20 6.8 fl oz
* For further details, see ªChanging Engine Oilº in MA section.
Preload
(At hub bolt)
N (kg, lb)Wheel bearing lock nut
78-98(8-10,58-72)
Tightening torque
N×m (kg-m, ft-lb)
Retightening torque after loosen-
ing wheel bearing lock nut
N×m (kg-m, in-lb)0.5 - 1.5 (0.05 - 0.15, 4.3 - 13.0)
Axial end play
mm (in)0 (0)
Starting force at wheel hub bolt
N (kg, lb)A
Turning angle
degree15É - 30É
Starting force at wheel hub bolt
N (kg, lb)B
Wheel bearing preload at wheel hub
bolt
B þ A N (kg, lb)7.06 - 20.99 (0.72 - 2.14, 1.59 - 4.72)

GENERAL INFORMATION
SECTION
GI
CONTENTS
PRECAUTIONS...............................................................3
Precautions ..................................................................3
PRECAUTIONS FOR SUPPLEMENTAL
RESTRAINT SYSTEM (SRS)²AIR BAG²AND
²SEAT BELT PRE-TENSIONER²
.................................3
PRECAUTIONS FOR IVIS (INFINITI VEHICLE
IMMOBILIZER SYSTEM - NATS)
.................................3
PRECAUTIONS FOR INFINITI COMMUNICATOR
(IVCS)
.......................................................................4
GENERAL PRECAUTIONS.........................................5
PRECAUTIONS FOR MULTIPORT FUEL
INJECTION SYSTEM OR ENGINE CONTROL
SYSTEM
...................................................................6
PRECAUTIONS FOR THREE WAY CATALYST...........6
PRECAUTIONS FOR HOSES.....................................7
PRECAUTIONS FOR ENGINE OILS...........................8
PRECAUTIONS FOR FUEL........................................8
PRECAUTIONS FOR AIR CONDITIONING..................8
HOW TO USE THIS MANUAL........................................9
HOW TO READ WIRING DIAGRAMS.......................... 11
Sample/Wiring Diagram - EXAMPL - ........................ 11
OPTIONAL SPLICE..................................................12
Description .................................................................13
CONNECTOR SYMBOLS.........................................15
HARNESS INDICATION...........................................16
COMPONENT INDICATION......................................16
SWITCH POSITIONS...............................................16
DETECTABLE LINES AND NON-DETECTABLE
LINES
.....................................................................17
MULTIPLE SWITCH.................................................18
REFERENCE AREA.................................................19
HOW TO CHECK TERMINAL.......................................21
Connector and Terminal Pin Kit.................................21
How to Probe Connectors .........................................21
PROBING FROM HARNESS SIDE............................21
PROBING FROM TERMINAL SIDE...........................21
How to Check Enlarged Contact Spring of
Terminal .....................................................................22
Waterproof Connector Inspection ..............................23
RUBBER SEAL INSPECTION...................................23
WIRE SEAL INSPECTION........................................23Terminal Lock Inspection ...........................................23
HOW TO PERFORM EFFICIENT DIAGNOSIS
FOR AN ELECTRICAL INCIDENT...............................24
Work Flow ..................................................................24
Incident Simulation Tests ...........................................25
INTRODUCTION......................................................25
VEHICLE VIBRATION..............................................25
HEAT SENSITIVE....................................................26
FREEZING..............................................................26
WATER INTRUSION................................................27
ELECTRICAL LOAD.................................................27
COLD OR HOT START UP.......................................27
Circuit Inspection .......................................................27
INTRODUCTION......................................................27
TESTING FOR²OPENS²IN THE CIRCUIT................28
TESTING FOR²SHORTS²IN THE CIRCUIT..............29
GROUND INSPECTION...........................................30
VOLTAGE DROP TESTS..........................................30
CONTROL UNIT CIRCUIT TEST...............................32
HOW TO FOLLOW TROUBLE DIAGNOSIS................34
How to Follow Test Groups in Trouble Diagnosis .....35
Key to Symbols Signifying Measurements or
Procedures.................................................................36
CONSULT-II CHECKING SYSTEM...............................38
Function and System Application ..............................38
Nickel Metal Hydride Battery Replacement...............39
Checking Equipment..................................................39
CONSULT-II Data Link Connector (DLC) Circuit ......40
INSPECTION PROCEDURE.....................................40
IDENTIFICATION INFORMATION................................41
Model Variation ..........................................................41
PREFIX AND SUFFIX DESIGNATIONS.....................41
Identification Number .................................................41
VEHICLE IDENTIFICATION NUMBER
ARRANGEMENT
.....................................................42
IDENTIFICATION PLATE..........................................42
ENGINE SERIAL NUMBER.......................................43
AUTOMATIC TRANSMISSION NUMBER...................43
TRANSFER SERIAL NUMBER..................................43
Dimensions ................................................................43
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IClean all disassembled parts in the designated liquid or solvent
prior to inspection or assembly.
IReplace oil seals, gaskets, packings, O-rings, locking washers,
cotter pins, self-locking nuts, etc. with new ones.
IReplace inner and outer races of tapered roller bearings and
needle bearings as a set.
IArrange the disassembled parts in accordance with their
assembled locations and sequence.
IDo not touch the terminals of electrical components which use
microcomputers (such as ECMs).
Static electricity may damage internal electronic components.
IAfter disconnecting vacuum or air hoses, attach a tag to indi-
cate the proper connection.
IUse only the fluids and lubricants specified in this manual.
IUse approved bonding agent, sealants or their equivalents
when required.
IUse tools and recommended special tools where specified for
safe and efficient service repairs.
IWhen repairing the fuel, oil, water, vacuum or exhaust
systems, check all affected lines for leaks.
IDispose of drained oil or the solvent used for cleaning parts in
an appropriate manner.
WARNING:
To prevent ECM from storing the diagnostic trouble codes, do
not carelessly disconnect the harness connectors which are
related to the engine control system and TCM (Transmission
Control Module) system. The connectors should be discon-
nected only when working according to the WORK FLOW of
TROUBLE DIAGNOSES in EC and AT sections.
SGI787
PRECAUTIONS FOR MULTIPORT FUEL INJECTION
SYSTEM OR ENGINE CONTROL SYSTEM
NBGI0001S03IBefore connecting or disconnecting any harness connector for
the multiport fuel injection system or ECM (Engine Control
Module):
Turn ignition switch to OFF position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.
IBefore disconnecting pressurized fuel line from fuel pump to
injectors, be sure to release fuel pressure.
IBe careful not to jar components such as ECM and mass air
flow sensor.
PRECAUTIONS FOR THREE WAY CATALYSTNBGI0001S04If a large amount of unburned fuel flows into the catalyst, the cata-
lyst temperature will be excessively high. To prevent this, follow the
instructions below:
IUse unleaded gasoline only. Leaded gasoline will seriously
damage the three way catalyst.
IWhen checking for ignition spark or measuring engine
compression, make tests quickly and only when necessary.
IDo not run engine when the fuel tank level is low, otherwise the
engine may misfire causing damage to the catalyst.
PRECAUTIONS
Precautions (Cont'd)
GI-6