Fuel system INFINITI QX56 2008 Factory Service Manual
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ECM
EC-477
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FUEL
SYSTEM
81H
Fuel injection system function
(Bank 1) P0171 or P0172 80H 2FH Long term fuel trim
P0171 or P0172 81H 24H
The number of lambda control
clamped
82H Fuel injection system function
(Bank 2) P0174 or P0175 80H 2FH Long term fuel trim
P0174 or P0175 81H 24H
The number of lambda control
clamped
Item
OBD-
MID Self-diagnostic test item
DTCTest value and Test
limit
(GST display) Description
TID Unit and
Scaling ID
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ENGINE CONTROL SYSTEM SYMPTOMSEC-481
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SYMPTOM DIAGNOSIS
ENGINE CONTROL SYSTEM SYMPTOMS
Symptom Matrix ChartINFOID:0000000001351340
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2EC-402
Fuel pressure regulator system 334444444 4 EC-494
Injector circuit11232 22 2EC-399
Evaporative emission system 334444444 4 EC-37
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-421
Incorrect idle speed adjustment 1 1 1 1 1EC-13
Electric throttle control actuator 112332222 2 2 EC-359
,
EC-362
,
EC-366
,
EC-368
IgnitionIncorrect ignition timing adjustment 33111 11 1EC-13
Ignition circuit 11222 22 2EC-411
Main power supply and ground circuit 22333 33 23 EC-83
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EC-482
< SYMPTOM DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Mass air flow sensor circuit
1
12 2
222 2 EC-106,
EC-113
Engine coolant temperature sensor circuit
333
EC-124,
EC-132
Air fuel ratio (A/F ) sensor 1 circuit EC-141
,
EC-145
,
EC-149
,
EC-153
,
EC-385
Throttle position sensor circuit
22EC-128
,
EC-194
,
EC-310
,
EC-312
,
EC-377
Accelerator pedal position sensor circuit 3 2 1EC-289
,
EC-370
,
EC-373
,
EC-381
Knock sensor circuit 23EC-204
Crankshaft position sensor (POS) circuit 2 2 EC-207
Camshaft position sensor (PHASE) circuit 3 2 EC-211
Vehicle speed signal circuit2 3 33EC-280
Power steering pressu re sensor circuit 23 3 EC-286
ECM 22333333333 EC-289,
EC-291
Intake valve timing control solenoid valve cir-
cuit 32 13223 3
EC-103
Park/Neutral position (PNP) signal circuit3 3 3 33EC-296
Refrigerant pressure sensor circuit 233 4 EC-423
Electrical load signal circuit 3EC-397
Air conditioner circuit 223333333 3 2 HAC-24
ABS actuator and electric unit (control unit) 4 BRC-37
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
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ENGINE CONTROL SYSTEM SYMPTOMSEC-483
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SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank 5
5 FL-11
Fuel piping
5 5 5 5 55FL-6
Va p o r l o c k —
Valve deposit 5 555 55 5—
Poor fuel (Heavy weight gasoline,
Low octane) —
Air Air duct
55555 5 EM-25
Air cleaner
EM-25
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555 EM-25
Electric throttle control actuator
EM-26
Air leakage from intake manifold/
Collector/GasketEM-26
Cranking Battery
111111
11
PG-73
Generator circuit
CHG-8
Starter circuit3 STR-8
Signal plate6 EM-45
Park/Neutral position (PNP) sig-
nal4
TM-43
Engine Cylinder head
55555 55 5 EM-68
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-82
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nism Timing chain
55555 55 5EM-45
Camshaft
EM-53
Intake valve timing controlEM-53
Intake valve
3EM-68
Exhaust valve
Revision: March 2010 2008 QX56
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EC-484
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ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.Exhaust Exhaust manifold/Tube/Muffler/
Gasket 55555 55 5EM-30
,
EX-
5Three way catalyst
Lubrica-
tion Oil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5EM-33
,
LU-
14 , LU-11 ,
LU-12
Oil level (Low)/Filthy oil LU-8, "In-
spection"
Cooling Radiator/Hose/Radiator filler cap
55555 55 45 CO-15
Thermostat
5CO-22
Water pump CO-20
Water galleryCO-6
Cooling fan5CO-18,
CO-
19
Coolant level (Low)/Contaminat-
ed coolant 5
CO-10
IVIS (INFINITI Vehicle Immobilizer System —
NATS) 11
SEC-8
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: March 2010 2008 QX56
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NORMAL OPERATING CONDITIONEC-485
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NORMAL OPERATING CONDITION
Fuel Cut Control (at No
Load and High Engine Speed)INFOID:0000000001351235
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
If the engine speed is above 1,800 rpm under no load (for example, the shift position is neutral and engine
speed over is 1,800 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies
based on engine speed.
Fuel cut will be operated until the engine speed reaches 1,500 rpm, then fuel cut will be cancelled.
NOTE:
This function is different from deceleration control listed under EC-28, "
System Description".
Sensor Input signal to ECMECM functionActuator
TCM Neutral position
Fuel cut control Fuel injector
Accelerator pedal position sensor
Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed
Wheel sensor Vehicle speed*
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PRECAUTIONSEC-487
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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
- <Flexible Fuel Vehicle>
Presumed ethanol mixture ratio
SEF289H
PBIB1164E
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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
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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
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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