2007 INFINITI QX56 fuel pressure

EM-56
< SERVICE INFORMATION >
CAMSHAFT
2. Perform the following procedure so as to prevent the engine from being unintentionally started while
checking.
a. Release fuel pressure. Refer to EC-80, "
Fuel Pressure Check".
b. Disconnect ignition coil and injector harness connectors if practical.
3. Remove IVT control solenoid valve.
4. Crank engine, and then make sure that engine oil comes out from IVT control cover oil hole. End cranking
after checking.
WARNING:
Be careful not to touch rotating parts (drive be lts, idler pulley, and crankshaft pulley, etc.).
CAUTION:
• Engine oil may squirt from IVT control soleno id valve installation hole during cranking. Use a
shop cloth to prevent engine oil from splashin g on worker, engine components and vehicle.
• Do not allow engine oil to get on rubber compon ents such as drive belts or engine mount insula-
tors. Immediately wipe off any splashed engine oil.
5. Clean oil groove between oil strainer and IVT control solenoid valve if engine oil does not come out from IVT control valve cover oil hole. Refer to LU-7, "
Schematic".
6. Remove components between IVT control solenoid va lve and camshaft sprocket (INT), and then check
each oil groove for clogging.
• Clean oil groove if necessary.
7. After inspection, installation of the remaining components is in the reverse order of removal.
Valve ClearanceINFOID:0000000003531536
INSPECTION
NOTE:
Perform the following inspection after removal, installation or replacement of camshaft or valve-related parts,
or if there are unusual engine conditions due to changes in valve clearance over time (starting, idling, and/or
noise).
1. Warm up the engine. Then stop the engine.
2. Remove the engine cover and. Refer to EM-12, "
Removal and Installation".
3. Remove the battery cover. Refer to SC-8, "
Removal and Installation".
4. Remove the air cleaner and air duct assembly EM-15, "
Removal and Installation".
5. Remove the RH bank and LH bank rocker covers using power tool. Refer to EM-35, "
Removal and Instal-
lation".
6. Turn the crankshaft pulley in the normal direction (clockwise when viewed from engine front) to align TDC identification notch
(without paint mark) with timing indicator.
KBIA2476E

EM-64
< SERVICE INFORMATION >
CYLINDER HEAD
CYLINDER HEAD
On-Vehicle ServiceINFOID:0000000003531540
CHECKING COMPRESSION PRESSURE
1. Warm up the engine thoroughly. Then stop the engine.
2. Release the fuel pressure. Refer to EC-80, "
Fuel Pressure Check".
CAUTION:
If CONSULT-II is not used to release fuel pressure leave the fu el pump fuse disconnected until
step 7.
3. Remove the spark plug from each cylinder. Refer to EM-29, "
Removal and Installation".
4. Connect the engine tachometer (not required in use of CONSULT-II).
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, che ck 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. R eplace the valve or valve seat accordingly.
• If two adjacent cylinders have respectively low co mpression 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-32
.
Tool number : EG15050500 (J-45402)
Standard Minimum
Deference limit be-
tween cylinders
1,520 (15.5, 220) / 200 1,324 (13.5, 192) / 200 98 (1.0, 14) / 200WBIA0605E

EM-74
< SERVICE INFORMATION >
ENGINE ASSEMBLY
ENGINE ASSEMBLY
Removal and InstallationINFOID:0000000003531544
WARNING:
• 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 the engine coolant. Refer to CO-9, "Changing Engine Coolant".
2. Partially drain the A/T fluid. Refer to AT-13, "
Changing Automatic Transmission Fluid (ATF)".
3. Release the fuel pressure. Refer to EC-80, "
Fuel Pressure Check".
4. Remove the engine hood. Refer to BL-12, "
Removal and Installation of Hood Assembly".
5. Remove the cowl extension. Refer to EI-17, "
Removal and Installation".
1. Rear engine mounting insulator 4WD 2. Rear engine mounting insulator 2WD 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

EM-76
< SERVICE INFORMATION >
ENGINE ASSEMBLY
a. Before removing the drive plate, put a match mark (A) on the
crankshaft and drive plate for alignment during installation.
b. Remove the drive plate.
• Holding the crankshaft pulley bolt, lock the crankshaft to remove the drive plate bolts.
• Loosen the bolts diagonally.
CAUTION:
• Be careful not to damage the drive plate. Especially
avoid deforming and damaging of the signal plate teeth
(circumference position).
• Place the drive plate with the signal plate surface facing
other than downward.
• Keep magnetic materials away from the signal plate.
CAUTION:
Use an engine stand that has a load capacity [approximately 240kg (529 lb) or more] large enough
for supporting the engine weight.
• 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 the fuel tube and fuel injector assembly. Refer to EM-31, "
Removal and Installation".
- Remove the intake manifold. Refer to EM-17, "
Removal and Installation".
- Remove the ignition coil. Refer to EM-28, "
Removal and Installation".
- Remove the rocker cover. Refer to EM-35, "
Removal and Installation".
- Other removable brackets.
CAUTION:
Before removing the hanging chains, make sure the engine stand is stable and there is no risk of
overturning.
31. Remove the generator. Refer to SC-22, "
Removal and Installation".
32. Remove the 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.
INSPECTION AFTER INSTALLATION
• Before starting the engine, check oil/fluid levels including engine coolant and engine oil. If the levels are
lower than required quantity, fill to the specified level. Refer to MA-10, "
Fluids and Lubricants".
• Use procedure below to check for fuel leakage.
• Turn ignition switch ON (with engine stopped). With fuel pressure applied to the fuel piping, check for fuel
leakage at the connection points.
ALBIA0522ZZ
KBIA2491E

FL-4
< SERVICE INFORMATION >
FUEL SYSTEM
FUEL SYSTEM
Checking Fuel LineINFOID:0000000003532203
Inspect fuel lines, fuel filler cap and fuel tank for improper attach-
ment, leaks, cracks, damage, loose connections, chafing or deterio-
ration.
If necessary, repair or replace damaged parts.
General PrecautionINFOID:0000000003532204
WARNING:
When replacing fuel line parts, be sure to observe the following.
• Put a “CAUTION: INFLAMMABLE” sign in the workshop.
• Be sure to work in a well ventilated area and furnish workshop with a CO
2 fire extinguisher.
• Do not smoke while servicing fuel system. Keep open flames and sparks away from the work area.
CAUTION:
• Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-proof container and put the lid on securely. Keep the container in
safe area.
- Release fuel pressure from the fuel lines. Refer to EC-80, "
Fuel Pressure Check" .
- Disconnect the battery negative terminal.
• Always replace O-rings and clamps with new ones.
• Do not kink or twist hoses when they are being installed.
• After connecting the fuel tube quick connectors, make sure
the quick connectors are secure.
Ensure that the connector and resin tube do not contact any
adjacent parts.
• After installing 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 con-
nections.
- Start the engine and rev it up and check for fuel leaks at con-
nections.
• Use only a Genuine NISSAN fuel filler cap as a replacement. If
an incorrect fuel filler cap is used, the MIL may come on.
• For servicing “Evaporative Emission System” parts, refer to
EC-33
.
• For servicing “On Board Refueling Vapor Recovery (ORVR)”
parts, refer to EC-40
.
SMA803A
PBIC1268E

FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
FL-5
< SERVICE INFORMATION >
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FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
Removal and InstallationINFOID:0000000003532205
REMOVAL
WARNING:
Follow the “General Precautions” before working on the fuel system. Refer to GI-3, "
General Precau-
tion" .
1. Remove the fuel filler cap to release the pressure from inside the fuel tank.
2. Check the fuel level on level gauge. If the fuel gauge indicates
more than the level as shown (full or almost full), drain the fuel
from the fuel tank until the fuel gauge indicates the level as
shown, or less.
• If the fuel pump does not operate, use the following procedure
to drain the fuel to the specified level.
a. Insert a suitable hose of less than 15 mm (0.59 in) diameter into
the fuel filler pipe through the fuel filler opening to drain the fuel
from fuel filler pipe.
b. Remove the LH rear wheel and tire. Refer to WT-7, "
Rotation" .
c. Remove the four clips and remove the rear fender protector,
front.
1. Inspection hole cover 2. Inspection hole cover O-ring 3. Lock ring
4. Fuel level sensor, fuel filter, and fuel
pump assembly5. Fuel tank 6. Fuel level sensor, fuel filter, and fuel
pump assembly O-ring
LBIA0381E
WBIA0390E

FL-6
< SERVICE INFORMATION >
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
d. Disconnect the fuel filler hose from the fuel filler pipe.
e. Insert a suitable hose into the fuel tank through the fuel filler hose to drain the fuel from the fuel tank.
• As a guide, the fuel level reaches the fuel gauge position as shown, or less, when approximately 14
liters (3 3/4 US gal, 3 1/8 Imp gal) of fuel are drained from the fuel tank.
3. Release the fuel pressure from the fuel lines. Refer to EC-80, "
Fuel Pressure Check" .
4. Disconnect the battery negative terminal.
5. Remove the second row LH seat and the third row LH seat. Refer to SE-89, "
Removal and Installation"
(second row), SE-95, "LH Side Seat" (third row).
6. Remove the second and third row rear seat belt buckles mounted on the floor. Refer to SB-3
.
7. Remove the LH center pillar trim, the LH rear trim panel, and the LH rear side door kick plate and weather
stripping. Refer to EI-34
.
8. Remove the second row rear center console and base, if equipped. Refer to EI-36
.
9. Reposition the floor carpet out of the way to access the inspection hole cover, located under the center LH
rear seat.
10. Remove the inspection hole cover by turning the retainers 90°
degrees clockwise.
• Remove the O-ring.
11. Disconnect the fuel level sensor, fuel filter, and fuel pump
assembly electrical connector, the EVAP hose, and the fuel feed
hose.
LBIA0386E
LBIA0382E
LBIA0383E

FL-8
< SERVICE INFORMATION >
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
12. Remove the lock ring using Tool.
13. Remove the fuel level sensor, fuel filter, and fuel pump assem-
bly. Remove and discard the fuel level sensor, fuel filter, and fuel
pump assembly O-ring.
CAUTION:
• Do not bend the float arm during removal.
• Avoid impacts such as dropping when handling the com-
ponents.
INSTALLATION
Installation is in the reverse order of removal.
• For installation, use a new fuel level sensor, fuel filter, and fuel pump assembly O-ring.
• Connect the quick connector as follows:
- Check the connection for any damage or foreign materials.
- Align the connector with the pipe, then insert the connector straight into the pipe until a click is heard.
- After connecting the quick connector, make sure that the connec-
tion is secure by checking as follows:
- Pull the tube and the connector to make sure they are securely
connected.
- Visually inspect the connector to make sure the two retainer tabs
are securely connected.
INSPECTION AFTER INSTALLATION
1. Turn the ignition switch ON but do not start engine, then check the fuel pipes and hose connections for
leaks while applying fuel pressure to the system.
2. Start the engine and rev it above idle speed, then check that there are no fuel leaks at any of the fuel pipe
and hose connections.Tool number : — (J-46536)
LBIA0389E
PBIC1653E