EM-58Revision: October 2005
CYLINDER HEAD
2005 QX56
CYLINDER HEADPFP:11041
On-Vehicle ServiceEBS00LME
CHECKING COMPRESSION PRESSURE
1. Warm up the engine thoroughly. Then stop the engine.
2. Release the fuel pressure. Refer to EC-93, "
FUEL PRESSURE RELEASE" .
CAUTION:
Leave the fuel pump fuse disconnected until step 7.
3. Remove the spark plug from each cylinder. Refer to EM-27, "
REMOVAL" .
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, 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, the 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-95, "
TROUBLE DIAGNOSIS" . Tool number : EG15050500 (J-45402)
Standard MinimumDeference limit
between cylinders
1,520 (15.5, 220) / 200 1,324 (13.5, 192) / 200 98 (1.0, 14) / 200
WBIA0605E
CYLINDER HEAD
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Removal and InstallationEBS00LMF
REMOVAL
1. Remove the engine assembly from the vehicle. Refer to EM-69, "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-19, "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 the crankshaft pulley, front cover, oil pump, and timing chain. Refer to EM-35, "
TIMING CHAIN" .
4. Remove the camshaft sprockets and camshafts. Refer to EM-43, "
CAMSHAFT" .
5. Remove the cylinder head bolts in reverse of 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
ENGINE ASSEMBLY
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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 fac-
ing 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-29, "REMOVAL" .
–Remove the intake manifold. Refer to EM-15, "REMOVAL" .
–Remove the ignition coil. Refer to EM-26, "REMOVAL" .
–Remove the rocker cover. Refer to EM-33, "REMOVAL" .
–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 alternator. Refer to SC-27, "
REMOVAL" .
32. Remove the engine mounting insulator and bracket using power tool.
KBIA2491E
EM-72Revision: October 2005
ENGINE ASSEMBLY
2005 QX56
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-11, "
RECOMMENDED 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.
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 fuel, exhaust gas, or any oils/fluids includ-
ing engine oil and engine coolant.
Bleed air from passages in lines and hoses, such as in cooling system.
After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. 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
Other oils and fluids* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gas — Leakage —
FL-4Revision: October 2005
FUEL SYSTEM
2005 QX56
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
connections.
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-32, "
EVAPORATIVE EMISSION SYSTEM" .
For servicing “On Board Refueling Vapor Recovery
(ORVR)” parts, refer to EC-39, "
ON BOARD REFUELING
VAPOR RECOVERY (ORVR)" .
PBIC1268E
FL-8Revision: October 2005
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
2005 QX56
11. Remove the lock ring using Tool.
12. Remove the fuel level sensor, fuel filter, and fuel pump assem-
bly.
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.
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 con-
nection 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
FUEL TANK
FL-13
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19. Remove the fuel tank strap bolts while supporting the fuel tank
with a suitable lift jack.
20. Disconnect the EVAP hose from the molded clip in the top of the fuel tank while lowering the fuel tank.
21. Lower the fuel tank using a suitable lift jack and remove it.
22. If necessary, remove the lock ring using Tool.
23. If necessary, remove the fuel level sensor, fuel filter, and fuel
pump assembly.
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.
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 con-
nection 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 pipe and hose connections for
leaks while applying fuel pressure.
2. Start the engine and rev it above idle, then check that there are no fuel leaks at any of the fuel pipe and
hose connections.
LBIA0387E
Tool number : — (J-46536)
LBIA0389E
PBIC1653E
PRECAUTIONS
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PRECAUTIONSPFP:00001
DescriptionEAS001F5
Observe the following precautions to ensure safe and proper servicing. These precautions are not
described in each individual section.
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EAS001F6
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 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 whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WA RN ING:
To avoid rendering the SRS inoperative, 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 per-
formed by an authorized NISSAN/INFINITI dealer.
Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for NVIS/IVIS (NISSAN/INFINITI VEHICLE IMMOBILIZER SYSTEM -
NATS) (If Equipped)
EAS001XP
NVIS/IVIS (NATS) will immobilize the engine if someone tries to start it without the registered key of NVIS/IVIS
(NATS).
Both of the originally supplied ignition key IDs have been NVIS/IVIS (NATS) registered.
The security indicator is located on the instrument panel. The indicator blinks when the immobilizer system is
functioning.
Therefore, NVIS/IVIS (NATS) warns outsiders that the vehicle is equipped with the anti-theft system.
When NVIS/IVIS (NATS) detects trouble, the security indicator lamp lights up while ignition switch is in
"ON" position.
This lighting up indicates that the anti-theft is not functioning, so prompt service is required.
When servicing NVIS/IVIS (NATS) (trouble diagnoses, system initialization and additional registration of
other NVIS/IVIS (NATS) ignition key IDs), CONSULT-II hardware and CONSULT-II NVIS/IVIS (NATS)
software is necessary.
Regarding the procedures of NVIS/IVIS (NATS) initialization and NVIS/IVIS (NATS) ignition key ID regis-
tration, refer to CONSULT-II operation manual, NVIS/IVIS (NATS).
Therefore, CONSULT-II NVIS/IVIS (NATS) software (program card and operation manual) must be kept
strictly confidential to maintain the integrity of the anti-theft function.
When servicing NVIS/IVIS (NATS) (trouble diagnoses, system initialization and additional registration of
other NVIS/IVIS (NATS) ignition key IDs), it may be necessary to re-register original key identification.
Therefore, be sure to receive all keys from vehicle owner. A maximum of four or five key IDs can be regis-
tered into NVIS/IVIS (NATS).
When failing to start the engine first time using the key of NVIS/IVIS (NATS), start as follows.
1. Leave the ignition key in "ON" position for approximately 5 seconds.
2. Turn ignition key to "OFF" or "LOCK" position and wait approximately 5 seconds.
3. Repeat step 1 and 2 again.
4. Restart the engine while keeping the key separate from any others on key-chain.