ignition INFINITI QX56 2004 Factory Service Manual
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SERVICE DATA AND SPECIFICATIONS (SDS)
EC-649
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Revision: August 20072004 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
Fuel PressureUBS00HE9
Idle Speed and Ignition TimingUBS00HEA
*1: Under the following conditions:
Air conditioner switch: OFF
Electric load: OFF (Lights and heater fan)
Steering wheel: Kept in straight-ahead position
Calculated Load ValueUBS00HEB
Mass Air Flow SensorUBS00HEC
*: Engine is warmed up to normal operating temperature and running under no-load.
Intake Air Temperature SensorUBS00HED
Engine Coolant Temperature SensorUBS00HEE
A/F Sensor 1 HeaterUBS00HEF
Heated Oxygen sensor 2 HeaterUBS00HEG
Crankshaft Position Sensor (POS)UBS00HEH
Refer to EC-260, "Component Inspection" .
Camshaft Position Sensor (PHASE)UBS00HEI
Refer to EC-266, "Component Inspection" .
Throttle Control MotorUBS00HEJ
Fuel pressure at idling kPa (kg/cm2 , psi)Approximately 350 (3.57, 51)
Target idle speed
No-load*1 (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-II or GST)
At idle14.0 - 33.0
At 2,500 rpm12.0 - 25.0
Supply voltage Battery voltage (11 - 14V)
Output voltage at idle1.1 - 1.4V*
Mass air flow (Using CONSULT-II 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)1.9 - 2.1
80 (176)0.31 - 0.37
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)] 3.3 - 4.3Ω
Resistance [at 25°C (77°F)] 5.0 - 7.0Ω
Resistance [at 25°C (77°F)] Approximately 1 - 15Ω
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EM-1
ENGINE MECHANICAL
B ENGINE
CONTENTS
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SECTION EM
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Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 3
Precautions for Drain Engine Coolant ...................... 3
Precautions for Disconnecting Fuel Piping .............. 3
Precautions for Removal and Disassembly ............. 3
Precautions for Inspection, Repair and Replace-
ment ......................................................................... 3
Precautions for Assembly and Installation ............... 3
Parts Requiring Angular Tightening ......................... 3
Precautions for Liquid Gasket .................................. 4
REMOVAL OF LIQUID GASKET SEALING .......... 4
LIQUID GASKET APPLICATION PROCEDURE ..... 4
PREPARATION ........................................................... 5
Special Service Tools ............................................... 5
Commercial Service Tools ........................................ 7
NOISE, VIBRATION, AND HARSHNESS (NVH)
TROUBLESHOOTING ................................................ 9
NVH Troubleshooting —Engine Noise ..................... 9
Use the Chart Below to Help You Find the Cause
of the Symptom. ..................................................... 10
ENGINE ROOM COVER ...........................................11
Removal and Installation .........................................11
REMOVAL ............................................................11
INSTALLATION ....................................................11
DRIVE BELTS ........................................................... 12
Checking Drive Belts .............................................. 12
Tension Adjustment ................................................ 12
Removal and Installation ........................................ 12
DRIVE BELT ....................................................... 12
INSTALLATION ................................................... 13
Drive Belt Auto Tensioner and Idler Pulley ............. 13
REMOVAL ........................................................... 13
INSTALLATION ................................................... 13
AIR CLEANER AND AIR DUCT ............................... 14
Removal and Installation ........................................ 14
REMOVAL ........................................................... 14
INSTALLATION ................................................... 14
CHANGING AIR CLEANER FILTER ................... 14INTAKE MANIFOLD ................................................. 15
Removal and Installation ........................................ 15
REMOVAL ........................................................... 15
INSTALLATION ................................................... 17
INSPECTION AFTER INSTALLATION ................ 18
EXHAUST MANIFOLD AND THREE WAY CATA-
LYST .......................................................................... 19
Removal and Installation ........................................ 19
REMOVAL ........................................................... 19
INSPECTION AFTER REMOVAL ....................... 20
INSTALLATION ................................................... 20
OIL PAN AND OIL STRAINER ................................. 22
Removal and Installation ........................................ 22
REMOVAL ........................................................... 22
INSPECTION AFTER REMOVAL ....................... 23
INSTALLATION ................................................... 24
INSPECTION AFTER INSTALLATION ................ 25
IGNITION COIL ......................................................... 26
Removal and Installation ........................................ 26
REMOVAL ........................................................... 26
INSTALLATION ................................................... 26
SPARK PLUG (PLATINUM-TIPPED TYPE) ............. 27
Removal and Installation ........................................ 27
REMOVAL ........................................................... 27
INSPECTION AFTER REMOVAL ....................... 27
INSTALLATION ................................................... 28
FUEL INJECTOR AND FUEL TUBE ........................ 29
Removal and Installation ........................................ 29
REMOVAL ........................................................... 29
INSTALLATION ................................................... 30
INSPECTION AFTER INSTALLATION ................ 32
ROCKER COVER ..................................................... 33
Removal and Installation ........................................ 33
REMOVAL ........................................................... 33
INSTALLATION ................................................... 34
TIMING CHAIN .......................................................... 35
Removal and Installation ........................................ 35
REMOVAL ........................................................... 36
INSPECTION AFTER REMOVAL ....................... 39
INSTALLATION ................................................... 39
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PRECAUTIONS
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PRECAUTIONSPFP:00001
Precautions for Drain Engine CoolantEBS00IKY
Drain engine coolant when engine is cooled.
Precautions for Disconnecting Fuel PipingEBS00IKZ
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.
Precautions for Removal and DisassemblyEBS00IL0
When instructed to use special service tools, use the specified 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 organized 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.
Precautions for Inspection, Repair and ReplacementEBS00IL1
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precautions for Assembly and InstallationEBS00IL2
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 the
ones in center, then ones on inside and outside diagonally in this order. If the order of tightening is speci-
fied, 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 speed to check engine coolant, fuel, oil, and exhaust
systems for leakage.
Parts Requiring Angular TighteningEBS00IL3
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)
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EM-18Revision: August 2007
INTAKE MANIFOLD
2004 QX56
5. Install the quick connector cap on the quick connector joint (on
engine side only).
6. Install the fuel hose and tube to hose clamps.
7. Refill the engine coolant. Refer to MA-13, "
REFILLING ENGINE
COOLANT" .
INSPECTION AFTER INSTALLATION
After installing fuel tubes, make sure there is no fuel leakage at connections in the following steps.
–Apply fuel pressure to fuel lines with turning ignition switch ON (with engine stopped). Then check for
fuel leaks at connections.
–Start the engine and rev it up and check for fuel leaks at connections.
Perform procedures for “Throttle Valve Closed Position Learning” after finishing repairs. Refer to EC-44,
"Throttle Valve Closed Position Learning" .
If electric throttle control actuator is replaced, perform procedures for “Idle Air Volume Learning” after fin-
ishing repairs. Refer to EC-44, "
Idle Air Volume Learning" .
SBIA0354E
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EM-26Revision: August 2007
IGNITION COIL
2004 QX56
IGNITION COILPFP:22448
Removal and InstallationEBS00ILI
REMOVAL
1. Remove the engine room cover using power tool. Refer to EM-11 .
2. Disconnect the harness connector from the ignition coil.
3. Remove ignition coil.
CAUTION:
Do not shock ignition coil.
INSTALLATION
Installation is in the reverse order of removal.
1. Ignition coil 2. Spark plug
KBIA2505E
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SPARK PLUG (PLATINUM-TIPPED TYPE)
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SPARK PLUG (PLATINUM-TIPPED TYPE)PFP:22401
Removal and InstallationEBS00ILJ
REMOVAL
1. Remove the ignition coil. Refer to EM-26, "REMOVAL" .
2. Remove the spark plug using suitable tool.
INSPECTION AFTER REMOVAL
Use standard type spark plug for normal condition.
The hot type spark plug is suitable when fouling occurs with the standard type spark plug under conditions
such as:
Frequent engine starts
Low ambient temperatures
The cold type spark plug is suitable when spark knock occurs with the standard type spark plug under condi-
tions such as:
Extended highway driving
Frequent high engine revolution
1. Ignition coil 2. Spark plug
KBIA2505E
SEM 29 4A
MakeNGK
Standard typePLFR5A-11
Hot typePLFR4A-11
Cold typePLFR6A-11
Gap (Nominal) : 1.1 mm (0.043 in)
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EM-32Revision: August 2007
FUEL INJECTOR AND FUEL TUBE
2004 QX56
Lubricate O-ring with new engine oil.
Do not clean O-ring with solvent.
Make sure that O-ring and its mating part are free of foreign material.
When installing O-ring, be careful not to scratch it with tool or fingernails. Also be careful not to
twist or stretch O-ring. If O-ring was stretched while it was being attached, do not insert it
quickly into fuel tube.
Insert new O-ring straight into fuel tube. Do not twist it.
6. Installation of the remaining components is in the reverse order of removal.
INSPECTION AFTER INSTALLATION
After installing the fuel tubes, make sure there are no fuel leaks at the connections using the following steps.
1. Apply fuel pressure to the fuel lines by turning the ignition switch ON (with engine stopped). Then check
for fuel leaks at the connections.
NOTE:
Use mirrors for checking on hidden points.
2. Start the engine and rev it up and check for fuel leaks at connections.
CAUTION:
Do not touch the engine immediately after stopping, as engine becomes extremely hot.
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ROCKER COVER
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ROCKER COVERPFP:13264
Removal and InstallationEBS00ILL
REMOVAL
1. Remove the engine room cover using power tool. Refer to EM-11, "REMOVAL" .
2. Remove the air duct and resonator assembly. Refer to EM-14, "
REMOVAL" (for left bank only) .
3. Move the harness on the upper rocker cover and its peripheral aside.
4. Remove the electric throttle control actuator, loosening bolts diagonally (for left bank only).
5. Remove the ignition coil. Refer to EM-26, "
REMOVAL" .
6. Remove the PCV hose from the PCV control valve.
7. Loosen the bolts in reverse order shown using power tool.
CAUTION:
Do not hold the rocker cover by the oil filler neck (right
bank).
1. Rocker cover (left bank) 2. PCV control valve 3. O-ring
4. Rocker cover gasket (left bank) 5. Rocker cover (right bank) 6. PCV control valve
7. O-ring 8. Oil filler cap 9. Rocker cover gasket (right bank)
KBIA2508E
KBIA2509E
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EM-36Revision: August 2007
TIMING CHAIN
2004 QX56
NOTE:
To remove timing chain and associated parts, start with those on the left bank. The procedure for remov-
ing parts on the right bank is omitted because it is the same as that for removal on the left bank.
To install timing chain and associated parts, start with those on the right bank. The procedure for installing
parts on the left bank is omitted because it is the same as that for installation on the right bank.
REMOVAL
1. Remove the engine assembly from the vehicle. Refer to EM-70, "REMOVAL" .
2. Remove the following components and related parts:
Drive belt auto tensioner and idler pulley. Refer to EM-12, "DRIVE BELTS" .
Thermostat housing and water hose. Refer to CO-17, "Removal of Thermostat Housing, Water Outlet
and Heater Pipe" .
Power steering pump bracket. Refer to PS-26, "REMOVAL" .
Oil pan (lower), (upper) and oil strainer. Refer to EM-22, "OIL PAN AND OIL STRAINER" .
Ignition coil. Refer to EM-26, "IGNITION COIL" .
Rocker cover. Refer to EM-33, "ROCKER COVER" .
3. Remove the chain case cover (right bank) and (left bank).
a. Loosen and remove the bolts in the reverse order shown.
b. Cut the liquid gasket to remove covers using Tool.
CAUTION:
Do not damage mating surfaces.
4. Obtain compression TDC of No. 1 cylinder as follows:
a. Turn crankshaft pulley clockwise to align the TDC identification
notch (without paint mark) with timing indicator on front cover.
1. Camshaft sprocket (left bank EXH) 2. Camshaft sprocket (left bank INT) 3. Camshaft sprocket (right bank INT)
4. Camshaft sprocket (right bank EXH) 5. Front cover 6. Chain case cover (right bank)
7. Chain case cover (left bank) 8. Crankshaft pulley bolt 9. Crankshaft pulley
10. Chain tensioner cover 11. Front oil seal 12. Oil pump drive spacer
13. Oil pump assembly 14. Crankshaft sprocket 15. Bracket
16. O-ring 17. Timing chain tension guide (right
bank)18. Timing chain slack guide (right bank)
19. Timing chain (right bank) 20. Timing chain (left bank) 21. Chain tensioner (right bank)
22. Timing chain slack guide (left bank) 23. Timing chain tension guide (left
bank)24. Chain tensioner (left bank)
Tool number: KV10111100 (J-37228)
KBIA2475E
KBIA2476E
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CYLINDER HEAD
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CYLINDER HEADPFP:11041
On-Vehicle ServiceEBS00ILS
CHECKING COMPRESSION PRESSURE
1. Warm up engine thoroughly. Then stop engine.
2. Release fuel pressure. Refer to EC-46, "
FUEL PRESSURE RELEASE" .
a. Remove fuel pump fuse, and start engine.
Refer to PG-78, "
FUSE AND RELAY BOX" or fuel pump fuse location.
Let fuel pump fuse removed until the end of step 7.
b. After engine stalls, crank it two or three times to release all fuel pressure.
3. Remove ignition coil and spark plug from each cylinder.
Refer to EM-27, "
REMOVAL" .
4. Connect engine tachometer (not required in use of CONSULT-II).
5. Install compression tester with Tool into spark plug hole.
6. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge
pointer stabilizes, read the compression pressure and engine rpm. Perform these steps to check each cyl-
inder.
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 specified range, check battery liquid for proper gravity. Check engine
speed again with normal battery gravity.
If compression pressure is below minimum value, check valve clearances and parts associated with
combustion chamber (valve, valve seat, piston, piston ring, cylinder bore, cylinder head, cylinder head
gasket). After the checking, measure compression pressure again.
If some cylinders have low compression pressure, pour 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, the piston rings may be worn out or damaged. Check
the piston rings and replace if necessary.
–If the compression pressure remains at 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 valve in adjacent cylinders may
be damaged. Inspect and repair as required.
7. After inspection is complete, install removed parts. Installation is in the reverse order of removal.
8. Start engine, and confirm that engine runs smoothly.
9. Perform trouble diagnosis. If DTC appears, erase it. Refer to EC-71, "
TROUBLE DIAGNOSIS" . Tool number : EG15050500 (J-45402)
WBIA0605E
Standard MinimumDeference limit
between cylinders
1,520 (15.5, 220) / 200 1,324 (13.5, 192) / 200 98 (1.0, 14) / 300