fuel INFINITI QX56 2004 Factory Service Manual
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FUEL INJECTOR AND FUEL TUBE
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Handle O-ring with bare hands. Never wear gloves.
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 O-ring straight into fuel tube. Do not angle or twist it.
3. Install the fuel injector to the fuel tube using the following steps.
a. Insert new clip into clip mounting groove on the fuel injector.
Insert clip so that lug “A” of fuel injector matches notch “A” of
the clip.
CAUTION:
Do not reuse clip. Replace it with a new one.
Do not allow the clip to interfere with the O-ring. If
interference occurs, replace the O-ring.
b. Insert the fuel injector into the fuel tube with the clip attached.
Insert it while matching it to the axial center.
Insert fuel injector so that lug “B” of fuel tube matches notch
“B” of the clip.
Make sure that the fuel tube flange is securely fixed in the
flange fixing groove on the clip.
c. Make sure that installation is complete by checking that fuel
injector does not rotate or come off.
Make sure that the protrusions of the fuel injectors are aligned
with the cutouts of the clips after installation.
4. Install the fuel tube and fuel injector assembly to the intake manifold.
CAUTION:
Do not let the tip of the injector nozzle come in contact with other parts.
Tighten fuel tube assembly bolts “a” to “b” in illustration in two
steps.
5. Install the fuel hose assembly.
Insert connectors straight, making sure that the axis is lined up with fuel tube side to prevent O-ring
from being damaged.
Tighten the bolts evenly in several steps.
Make sure that there is no gap between the flange and fuel tube after tightening the bolts.
CAUTION:
Handle O-ring with bare hands. Do not wear gloves.Fuel tube side : Blue
Nozzle side : Brown
KBIA2507E
1st step : 12.8 N·m (1.3 kg-m, 9 ft-lb)
2nd step : 24.5 N·m (2.5 kg-m, 18 ft-lb)
KBIA2474E
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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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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
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EM-60Revision: August 2007
CYLINDER HEAD
2004 QX56
Removal and InstallationEBS00ILT
REMOVAL
1. Remove engine assembly from vehicle. Refer to EM-70, "REMOVAL" .
2. Remove the following components and related parts:
Auto tensioner of drive belts and idler pulley. Refer to EM-12, "DRIVE BELTS" .
Thermostat housing and hose. Refer to CO-17, "Removal of Thermostat Housing, Water Outlet and
Heater Pipe" .
Oil pan and oil strainer. Refer to EM-22, "OIL PAN AND OIL STRAINER" .
Fuel tube and fuel injector assembly. Refer to EM-29, "FUEL INJECTOR AND FUEL TUBE" .
Intake manifold. Refer to EM-15, "INTAKE MANIFOLD" .
Ignition coil. Refer to EM-26, "IGNITION COIL" .
Rocker cover. Refer to EM-33, "ROCKER COVER" .
3. Remove crankshaft pulley, front cover, oil pump, and timing chain. Refer to EM-35, "
TIMING CHAIN" .
4. Remove camshaft sprockets and camshafts. Refer to EM-43, "
CAMSHAFT" .
5. Remove cylinder head bolts in reverse order shown.
1. Harness bracket 2. Engine coolant temperature sensor 3. Washer
4. Cylinder head gasket (left bank) 5. Cylinder head (right bank) 6. Cylinder head bolt
7. Cylinder head gasket (right bank) 8. Cylinder head (left bank)
KBIA2528E
PBIC0068E
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EM-70Revision: August 2007
ENGINE ASSEMBLY
2004 QX56
ENGINE ASSEMBLYPFP:10001
Removal and InstallationEBS00ILW
WAR NIN G:
Situate vehicle on a flat and solid surface.
Place chocks at front and back of rear wheels.
For engines not equipped with engine slingers, attach proper slingers and bolts described in
PARTS CATALOG.
CAUTION:
Always be careful to work safely, avoid forceful or uninstructed operations.
Do not start working until exhaust system and engine coolant are cooled sufficiently.
If items or work required are not covered by the engine section, refer to the applicable sections.
Always use the support point specified for lifting.
Use either 2-point lift type or separate type lift. If board-on type is used for unavoidable reasons,
support at the rear axle jacking point with transmission jack or similar tool before starting work, in
preparation for the backward shift of center of gravity.
For supporting points for lifting and jacking point at rear axle, refer to GI-40, "Garage Jack and
Safety Stand" .
REMOVAL
Preparation
1. Drain engine coolant. Refer to MA-12, "DRAINING ENGINE COOLANT" .
2. Partially drain A/T fluid. Refer to AT - 1 3 , "
Changing A/T Fluid" .
3. Release fuel pressure. Refer to EC-46, "
FUEL PRESSURE RELEASE" .
4. Remove the engine hood. Refer to BL-12, "
HOOD" .
1. Rear engine mounting insulator 4x4 2. Rear engine mounting insulator 4x2 3. LH engine mounting bracket
4. LH heat shield plate 5. LH engine mounting insulator 6. RH engine mounting bracket
7. RH heat shield plate 8. RH engine mounting insulator
LBIA0397E
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ENGINE ASSEMBLY
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5. Remove the cowl extension. Refer to EI-18, "Removal and Installation" .
6. Remove engine room cover using power tools.
7. Remove the air duct and air cleaner case assembly. Refer to EM-14, "
REMOVAL" .
8. Disconnect vacuum hose between vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-10, "
REMOVAL" .
10. Remove the drive belts. Refer to EM-12, "
Removal" .
11. Remove the fan blade. Refer to CO-13, "
REMOVAL" .
12. Disconnect the engine room harness from the fuse box and set it aside for easier work.
13. Disconnect the ECM.
14. Disconnect the engine room harness from the engine side and set it aside for easier work.
15. Disconnect the engine harness grounds.
16. Disconnect the reservoir tank for power steering from engine and move it aside for easier work.
17. Disconnect power steering oil pump from engine. Move it from its location and secure with a rope for eas-
ier work. Refer to PS-26, "
REMOVAL" .
18. Remove the A/C compressor bolts and set aside. Refer to ATC-166, "
REMOVAL" .
19. Disconnect brake booster vacuum line.
20. Disconnect EVAP line.
21. Disconnect the fuel hose at the engine side connection. Refer to EM-29, "
REMOVAL" .
22. Disconnect the heater hoses at cowl, and install plugs to avoid leakage of engine coolant.
23. Remove the A/T oil level indicator and indicator tube upper bolts.
24. Remove the A/T. Refer to AT-255, "
Removal and Installation (4x2)" , or AT-258, "Removal and Installation
(4x4)" .
25. Install engine slingers into left bank cylinder head and right bank
cylinder head.
26. Lift with hoist and secure the engine in position.
27. Remove engine assembly from vehicle, avoiding interference
with vehicle body.
CAUTION:
Before and during this lifting, always check if any har-
nesses are left connected.
28. Remove alternator. Refer to SC-27, "
REMOVAL" .
29. Remove engine mounting insulator and bracket using power tool.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
When replacing an engine or transmission you must make sure the dowels are installed correctly
during re-assembly.
Improper alignment caused by missing dowels may cause vibration, oil leaks or breakage of driv-
etrain components.
WBIA0464E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
PBIC1556E
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EM-72Revision: August 2007
ENGINE ASSEMBLY
2004 QX56
INSPECTION AFTER INSTALLATION
Before starting engine, check the levels of engine coolant, engine oil and working fluid. If less than
required quantity, fill to the specified level.
Use procedure below to check for fuel leakage.
Turn ignition switch ON (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.
Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of engine coolant, engine oil, working fluid,
fuel and exhaust gas.
Bleed air from passages in pipes and tubes of applicable lines, such as in cooling system.
After cooling down engine, again check amounts of engine coolant, engine oil and working fluid. Refill to
specified level, if necessary.
Summary of the inspection items:
*Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.Item Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Working fluid* Level Leakage Level
Fuel — Leakage —
Exhaust gas — Leakage —
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CYLINDER BLOCK
2004 QX56
* Refer to GI-45, "Recommended Chemical Products and Sealants" .
DISASSEMBLY
1. Remove engine assembly. Refer to EM-70, "REMOVAL" .
2. Remove the drive plate.
Hold the crankshaft pulley bolt to lock the crankshaft and remove the drive plate bolts.
Loosen bolts diagonally.
CAUTION:
Be careful not to damage drive plate. Especially avoid
deforming and damaging of signal plate teeth (circum-
ference position).
Place the drive plate with signal plate surface facing
other than downward.
Keep magnetic materials away from signal plate.
3. Lift the engine with hoist to install it onto engine stand. Refer to EM-70, "
REMOVAL" .
CAUTION:
Use an engine stand that has a load capacity [approximately 240kg (529 lb) or more] large
enough for supporting the engine weight.
Before removing the hanging chains, make sure the engine stand is stable and there is no risk
of overturning.
If the load capacity of the stand is not adequate, remove the following parts beforehand to reduce the
potential risk of overturning the stand.
–Remove fuel tube and fuel injector assembly. Refer to EM-29, "REMOVAL" .
–Remove intake manifold. Refer to EM-15, "REMOVAL" .
–Remove exhaust manifold. Refer to EM-19, "REMOVAL" .
–Remove A/C compressor fitting bolts and brackets. Refer to ATC-166, "REMOVAL" .
–Remove ignition coil. Refer to EM-26, "REMOVAL" .
–Remove rocker cover. Refer to EM-33, "REMOVAL" .
–Other removable brackets.
4. Drain engine oil. Refer to MA-16, "
Changing Engine Oil" .
1. Knock sensor sub-harness 2. Knock sensor 3. Cylinder block
4. Main bearing 5. Top ring 6. Second ring
7. Oil ring 8. Crankshaft key 9. Piston
10. Connecting rod 11. Snap ring 12. Piston pin
13. Connecting rod bearing 14. Connecting rod bearing cap 15. Main bearing cap
16. Thrust bearing 17. Main bearing 18. Crankshaft
19. Pilot converter 20. Thrust bearing 21. Side bolt
22. Drive plate 23. Reinforcement plate 24. Rear oil seal retainer
25. Rear oil seal 26. Transmission 27. O-ring
28. Crankshaft position sensor (POS) 29. Gasket 30. Cylinder block heater
31. Connector cap
KBIA2491E
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FL-1
FUEL SYSTEM
B ENGINE
CONTENTS
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SECTION FL
A
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Revision: August 20072004 QX56 PREPARATION ........................................................... 2
Special Service Tools ............................................... 2
Commercial Service Tool ......................................... 2
FUEL SYSTEM ........................................................... 3
Checking Fuel Lines ................................................. 3
General Precautions ................................................ 3
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND
FUEL PUMP ASSEMBLY ........................................... 5
Removal and Installation .......................................... 5
REMOVAL ............................................................. 5
INSTALLATION ..................................................... 8
INSPECTION AFTER INSTALLATION ................. 8FUEL TANK ................................................................ 9
Removal and Installation .......................................... 9
REMOVAL ........................................................... 10
INSTALLATION ................................................... 13
INSPECTION AFTER INSTALLATION ................ 13
SERVICE DATA AND SPECIFICATIONS (SDS) ...... 14
Standard and Limit .................................................. 14
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FL-2Revision: August 2007
PREPARATION
2004 QX56
PREPARATIONPFP:00002
Special Service ToolsEBS00IKL
The actual shapes of the Kent-Moore tools may differ from those of the special tools illustrated here.
Commercial Service ToolEBS00IKM
Tool number
(Kent-Moore No.)
Tool nameDescription
—
(J-46536)
Fuel tank lock ring toolRemoving and installing fuel tank lock ring
LBIA0398E
Tool nameDescription
Power toolLoosening bolts and nuts
PBIC0190E