ignition INFINITI QX56 2008 Factory Service Manual

EC-486
< PRECAUTION >[VK56DE]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint Syst
em (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006054103
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000006211820
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56

PRECAUTIONSEC-487
< PRECAUTION > [VK56DE]
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5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
On Board Diagnosis (OBD) System of Engine and A/TINFOID:0000000001351222
The ECM has an on board diagnostic system . It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch OFF and di sconnect the negative battery cable before any repair
or inspection work. The open/short circuit of re lated switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
• Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For description and how to disconnect, refer to PG-65
.
• Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to li ght up due to the short circuit.
• Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfuncti on of the EVAP system or fuel injection system,
etc.
• Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and TCM (Transmission control module) before returning the vehicle to the customer.
PrecautionINFOID:0000000006211821
•Always use a 12 volt battery as power source.
• Do not attempt to disconnect battery cables while engine is
running.
• Before connecting or disc onnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
• Before removing parts, turn ig nition switch OFF and then dis-
connect negative battery cable.
• Do not disassemble ECM.
• If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to sel f-control at its initial value.
Engine operation can vary slight ly when the terminal is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.
• If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
-
Presumed ethanol mixture ratio
SEF289H
PBIB1164E
Revision: March 2010 2008 QX56

EC-494
< ON-VEHICLE MAINTENANCE >[VK56DE]
FUEL PRESSURE
ON-VEHICLE MAINTENANCE
FUEL PRESSURE
Fuel Pressure CheckINFOID:0000000001351336
FUEL PRESSURE RELEASE
With CONSULT-IIl
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in
“WORK SUPPORT” mode with CONSULT-IIl.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
Without CONSULT-IIl
1. Remove fuel pump fuse located in IPDM E/R.
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
FUEL PRESSURE CHECK
CAUTION:
• Before disconnecting fuel line, release fuel pr essure from fuel line to eliminate danger.
• Be careful not to scratch or get the fuel hose connection area dirty wh en servicing, so that the quick
connector o-ring ma intains sealability.
• Use Fuel Pressure Gauge Kit J-44321 and Fuel Pr essure Adapter J-44321-6 to check fuel pressure.
• Do not perform fuel pressure check with electrical system operating (i.e. lights, rear defog, A/C, etc.).
Fuel pressure gauge may indicate false readings du e to varying engine loads and changes in mani-
fold vacuum.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pres-
sure cannot be completely released because JA60 models do not have fuel return system.
1. Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".
2. Remove engine cover.
3. Remove fuel hose using Quick Connector Release J-45488. Refer to EM-26
.
• Do not twist or kink fuel hose because it is plastic hose.
• Do not remove fuel hose from quick connector.
• Keep fuel hose connections clean.
4. Install Fuel Pressure Adapter J-44321-6 and Fuel Pressure Gauge (from kit J-44321) as shown in figure.
• Do not distort or bend fuel rail tube when installing fuel pres-sure gauge adapter.
• When reconnecting fuel hose, check the original fuel hose for damage and abnormality.
5. Turn ignition switch ON (reactivate fuel pump), and check for fuel leakage.
6. Start engine and check for fuel leakage.
7. Read the indication of fuel pressure gauge. • During fuel pressure check, check for fuel leakage from fuelconnection every 3 minutes.
BBIA0380E
BBIA0390E
Revision: March 2010 2008 QX56

EC-496
< ON-VEHICLE MAINTENANCE >[VK56DE]
EVAP LEAK CHECK
EVAP LEAK CHECK
How to Detect Fuel Vapor LeakageINFOID:0000000001351309
CAUTION:
• Never use compressed air or a high pressure pump.
• Do not exceed 4.12 kPa (0.042 kg/cm
2, 0.6 psi) of pressure in EVAP system.
NOTE:
• Do not start engine.
• Improper installation of EVAP service port adapter to the EVAP service port may cause a leak.
WITH CONSULT-IIl
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Also attach the pressure pump and hose to the EVAP service port adapter.
3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE” of “WORK SUPPORT MODE” with CONSULT-IIl.
5. Touch “START”. A bar graph (Pressure indicating display) will appear on the screen.
6. Apply positive pressure to the EVAP system until t he pressure indicator reaches the middle of the bar
graph.
7. Remove EVAP service port adapter and hose with pressure pump.
8. Locate the leak using a leak detector. Refer to EC-37, "
Descrip-
tion".
WITHOUT CONSULT-IIl
1. Attach the EVAP service port adapter securely to the EVAP ser- vice port.
2. Also attach the pressure pump with pressure gauge to the EVAP service port adapter.
SEF200U
BBIA0366E
SEF462UA
Revision: March 2010 2008 QX56

SERVICE DATA AND SPECIFICATIONS (SDS)EC-503
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SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
Fuel PressureINFOID:0000000001366032
Idle Speed and Ignition TimingINFOID:0000000001366033
*: Under the following conditions:
• Air conditioner switch: OFF
• Electric load: OFF (Lights and heater fan)
• Steering wheel: Kept in straight-ahead position
Calculated Load ValueINFOID:0000000001366034
Mass Air Flow SensorINFOID:0000000001366035
*: Engine is warmed up to normal operating temperature and running under no load.
Intake Air Temperature SensorINFOID:0000000001366036
Engine Coolant Temperature SensorINFOID:0000000001366037
A/F Sensor 1 HeaterINFOID:0000000001366038
Fuel pressure at idling kPa (kg/cm2, psi)
Approximately 350 (3.57, 51)
Target idle speed
No-load* (in P or N position) 650±50 rpm
Air conditioner: ON In P or N position 700 rpm or more
Ignition timing In P or N position 15° ± 5 ° BTDC
Condition Calculated load value % (Using CONSULT-IIl or GST)
At idle 14.0 - 33.0
At 2,500 rpm 12.0 - 25.0
Supply voltageBattery voltage (11 - 14V)
Output voltage at idle 1.0 - 1.3V*
Mass air flow (Using CONSULT-IIl or GST) 3.0 - 9.0 g·m/sec at idle*
9.0 - 28.0 g·m/sec at 2,500 rpm*
Temperature °C ( °F) Resistance kΩ
25 (77) 1.800 - 2.200
Temperature °C ( °F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Resistance [at 25°C (77 °F)] 1.98 - 2.66Ω
Revision: March 2010 2008 QX56

EM-1
ENGINE
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SECTION EM
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CONTENTS
ENGINE MECHANICAL
PRECAUTION ....... ........................................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
3
Precaution for Drain Engine Coolant .........................4
Precaution for Disconnecting Fuel Piping .................4
Precaution for Removal and Disassembly ................4
Precaution for Inspection, Repair and Replace-
ment .................................................................... ......
4
Precaution for Assembly and Installation ..................4
Parts Requiring Angular Tightening ..........................4
Precaution for Liquid Gasket ............................... ......5
PREPARATION ............................................6
PREPARATION .............................................. .....6
Special Service Tool ........................................... ......6
Commercial Service Tool ..........................................8
FUNCTION DIAGNOSIS ..............................10
NOISE, VIBRATION, AND HARSHNESS
(NVH) TROUBLESHOOTING ........................ ....
10
NVH Troubleshooting - Engine Noise ................. ....10
Use the Chart Below to Help You Find the Cause
of the Symptom .......................................................
11
ON-VEHICLE MAINTENANCE ....................13
DRIVE BELTS ................................................ ....13
Checking Drive Belts ........................................... ....13
Removal and Installation .........................................13
Drive Belt Auto Tensioner and Idler Pulley ......... ....14
AIR CLEANER FILTER ......................................15
Removal and Installation (Viscous paper type) ... ....15
SPARK PLUG ................................................ ....16
Removal and Installation ..................................... ....16
CAMSHAFT VALVE CLEARANCE ..................18
Valve Clearance ......................................................18
COMPRESSION PRESSURE ...........................23
Checking Compression Pressure ............................23
ON-VEHICLE REPAIR .................................24
ENGINE ROOM COVER ...................................24
Removal and Installation ..................................... ....24
AIR CLEANER AND AIR DUCT .......................25
Removal and Installation .........................................25
INTAKE MANIFOLD .........................................26
Removal and Installation .........................................26
EXHAUST MANIFOLD AND THREE WAY
CATALYST ........................................................
30
Exploded View .........................................................30
Removal and Installation .........................................30
OIL PAN AND OIL STRAINER .........................33
Removal and Installation .........................................33
IGNITION COIL .................................................37
Removal and Installation .........................................37
ROCKER COVER .............................................38
Removal and Installation .........................................38
FUEL INJECTOR AND FUEL TUBE ................40
Removal and Installation .........................................40
TIMING CHAIN ..................................................44
Components ........................................................ ....44
Removal and Installation .........................................45
CAMSHAFT .......................................................53
Components ............................................................53
Removal and Installation .........................................53
Revision: March 2010 2008 QX56

PRECAUTIONSEM-3
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004857552
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers, always switch the Ignition OFF, disconnect the battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wheel Rotation After Battery Disconnect
INFOID:0000000004857588
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecti ng both battery cables with the ignition knob in the
″ LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS , an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery power is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56

EM-4
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Precaution for Drain Engine CoolantINFOID:0000000001538794
Drain engine coolant when engine is cooled.
Precaution for Disconnecting Fuel PipingINFOID:0000000001538795
• Before starting work, make sure no fire or spark producing items are in the work area.
• Release fuel pressure before disconnecting and disassembly.
• After disconnecting pipes, plug openings to stop fuel leakage.
Precaution for Removal and DisassemblyINFOID:0000000001538796
• When instructed to use special service tools, use the s pecified tools. Always be careful to work safely, avoid
forceful or uninstructed operations.
• Exercise maximum care to avoid damage to mating or sliding surfaces.
• Cover openings of engine system with tape or the equivalent, if necessary, to seal out foreign materials.
• Mark and arrange disassembly parts in an organi zed way for easy troubleshooting and assembly.
• When loosening nuts and bolts, as a basic rule, start with the one furthest outside, then the one diagonally opposite, and so on. If the order of loosening is specified, do exactly as specified. Power tools may be used
where noted in the step.
Precaution for Inspection, Repair and ReplacementINFOID:0000000001538797
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precaution for Assembly and InstallationINFOID:0000000001538798
• Use torque wrench to tighten bolts or nuts to specification.
• When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with theones in center, then ones on inside and outside diagonally in this order. If the order of tightening is specified,
do exactly as specified.
• Replace with new gasket, packing, oil seal or O-ring.
• Thoroughly wash, clean, and air-blow each part. Carefully check engine oil or engine coolant passages for any restriction and blockage.
• Avoid damaging sliding or mating surfaces. Completely remove foreign materials such as cloth lint or dust. Before assembly, oil sliding surfaces well.
• Release air within route when refilling after draining engine coolant.
• Before starting engine, apply fuel pressure to fuel lines with turning ignition switch ON (with engine stopped). Then make sure that there are no leaks at fuel line connections.
• After repairing, start engine and increase engine s peed to check engine coolant, fuel, oil, and exhaust sys-
tems for leakage.
Parts Requiring Angular TighteningINFOID:0000000001538799
• For final tightening of the following engine parts use Tool:
- Cylinder head bolts
- Main bearing cap bolts
- Connecting rod cap bolts
- Crankshaft pulley bolt (No angle wrench is required as the bolt flange is provided with notches for angle tightening)
• Do not use a torque value for final tightening.
• The torque value for these parts are for a preliminary step.
• Ensure thread and seat surfaces are clean and lightly coated with engine oil. Tool number : KV10112100 (BT-8653-A)
Revision: March 2010
2008 QX56

EM-16
< ON-VEHICLE MAINTENANCE >
SPARK PLUG
SPARK PLUG
Removal and InstallationINFOID:0000000001538809
REMOVAL
1. Remove engine room cover using power tool. Refer to EM-24, "Removal and Installation".
2. Remove ignition coil. Refer to EM-37, "
Removal and Installation".
3. Remove spark plug using suitable tool.
INSPECTION AFTER REMOVAL
• Do not use a wire brush for cleaning.
• If plug tip is covered with carbon, spark plug cleaner may be used.
1. Ignition coil 2. Spark plug
WBIA0796E
SEM294A
Cleaner air pressure:
Less than 588 kPa (5.9 bar, 6 kg/cm
2 , 85 psi)
Cleaning time: Less than 20 seconds
SMA773C
Revision: March 2010 2008 QX56

COMPRESSION PRESSUREEM-23
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COMPRESSION PRESSURE
Checking Compression PressureINFOID:0000000001538811
1. Warm up the engine thoroughly. Then stop the engine.
2. Release the fuel pressure. Refer to EC-494, "
Fuel Pressure Check".
CAUTION:
If CONSULT-III is not used to release fuel pressure leave the fuel pump fuse disconnected until
step 7.
3. Remove the spark plug from each cylinder. Refer to EM-16, "
Removal and Installation".
4. Connect the engine tachometer (not required in use of CONSULT-III).
5. Install the compression tester with Tool into the spark plug hole.
6. With the accelerator pedal fully depressed, turn the ignition switch to “START” for cranking. When the gauge pointer stabi-
lizes, read the compression pressure and engine rpm. Perform
these steps to check each cylinder.
Unit: kPa (kg/cm2, psi) /rpm
CAUTION:
Always use a fully charged battery to obtain specified engine speed.
• If the engine speed is out of the specified range, check the battery liquid for proper gravity. Check the engine speed again with normal battery gravity.
• If the compression pressure is below the minimum value, check the valve clearances and parts associ-
ated with the combustion chamber (valve, valve seat , piston, piston ring, cylinder bore, cylinder head,
cylinder head gasket). After checking, measure the compression pressure again.
• If some cylinders have low compression pressure, pour a small amount of engine oil into the spark plug hole of the cylinder to re-check it for compression.
- If the added engine oil improves the compression, t he piston rings may be worn out or damaged. Check
the piston rings and replace if necessary.
- If the compression pressure remains at a low level despite the addition of engine oil, the valves may be malfunctioning. Check the valves for damage. Replace the valve or valve seat accordingly.
• If two adjacent cylinders have respectively low compression pressure and their compression remains low even after the addition of engine oil, the gaskets may be leaking, or a valve in adjacent cylinders
may be damaged. Inspect and repair as required.
7. Install the components in the reverse order of removal.
8. Start the engine and confirm that it runs smoothly.
9. Perform trouble diagnosis. If DTC appears, erase it. Refer to EC-75, "
Description".
Tool number : EG15050500 (J-45402)
Standard
MinimumDeference limit be-
tween cylinders
1,520 (15.5, 220) / 200 1,324 (13.5, 192) / 200 98 (1.0, 14) / 200WBIA0605E
Revision: March 2010 2008 QX56