2004 INFINITI QX56 spark plugs replace

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
TROUBLE DIAGNOSISPFP:00004
Trouble Diagnosis IntroductionUBS00GZW
INTRODUCTION
The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, or other malfunctions with the engine.
It is much more difficult to diagnose an incident that occurs intermit-
tently rather than continuously. Most intermittent incidents are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-II (or GST) or a circuit tester connected should
be performed. Follow EC-72, "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Diagnostic Worksheet like the example
on EC-75
should be used.
Start your diagnosis by looking for conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.
MEF036D
SEF 2 33 G
SEF 2 34 G

EC-246Revision: August 2007
DTC P0300 - P0308 MULTIPLE CYLINDER MISFIRE, NO. 1 - 8 CYLINDER MIS-
FIRE
2004 QX56
5. CHECK IGNITION SPARK
1. Turn ignition switch OFF.
2. Remove ignition coil assembly from rocker cover.
3. Remove spark plug from ignition coil assembly.
4. Connect a known-good spark plug to the ignition coil.
5. Disconnect all injector harness connectors.
6. Place end of spark plug against a suitable ground and crank engine.
7. Check for spark.
OK or NG
OK >> GO TO 6.
NG >> Check ignition coil, power transistor and their circuits.
Refer to EC-583, "
IGNITION SIGNAL" .
6. CHECK SPARK PLUGS
Remove the spark plugs and check for fouling, etc.
OK or NG
OK >> GO TO 7.
NG >> Repair or replace spark plug(s) with standard type
one(s). For spark plug type, refer to MA-17, "
Changing
Spark Plugs" .
7. CHECK COMPRESSION PRESSURE
Check compression pressure. Refer to EM-59, "
CHECKING COMPRESSION PRESSURE" .
OK or NG
OK >> GO TO 8.
NG >> Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
SEF 5 75 Q
SEF 1 56 I
Standard:
1,520 kPa (15.5 kg/cm2 , 220 psi)/200 rpm
Minimum:
1,324 kPa (13.5 kg/cm
2 , 192 psi)/200 rpm
Difference between each
cylinder:98 kPa (1.0 kg/cm
2 , 14 psi)/200 rpm

EM-64Revision: August 2007
CYLINDER HEAD
2004 QX56
8. Install valve collet using Tool.
CAUTION:
When working, take care not to damage valve lifter holes.
9. Install valve lifters.

Install removed parts in there original locations.

If installing new lifters, select the correct size lifter for proper
valve clearance. Refer to EM-52, "
Valve Clearance" .
10. Install spark plug tube if necessary, following the procedure below.
a. Remove old liquid gasket adhering to cylinder-head spark plug tube hole.
b. Apply liquid gasket to area within approximately 12 mm (0.47 in) from edge of spark plug tube press-fit
side.
Use Genuine RTV Silicone Sealant or equivalent. Refer to GI-45, "
Recommended Chemical Prod-
ucts and Sealants" .
c. Press-fit spark plug tube to specified height “H” using suitable
tool.
CAUTION:

When press-fitting, take care not to deform spark plug
tube.

After press-fitting, wipe off liquid gasket protruding onto
cylinder-head upper face.
11. Install spark plugs.
Inspection After DisassemblyEBS00ILV
CYLINDER HEAD DISTORTION
1. Remove any oil, scale, gasket, sealant and carbon deposits from the cylinder head surface.
CAUTION:
Do not allow any debris to enter the oil or coolant passages.
2. Measure the bottom surface of cylinder head for distortion in six
directions as shown.

If measurement exceeds the limit, replace cylinder head.Tool number : KV10116200 (J-26336-B)
: KV10115900 (J-26336-20)
: KV10109220 ( — )
Standard press-fit height “H” :38.4 - 39.4 mm
(1.512 - 1.551 in)
WBIA0578E
KBIA1248E
Standard : 0.03 mm (0.0012 in)
Limit : 0.1mm (0.004 in)
PBIC0075E

MA-6
PERIODIC MAINTENANCE
Revision: August 20072004 QX56
PERIODIC MAINTENANCEPFP:00026
Introduction of Periodic MaintenanceELS00100
Two different maintenance schedules are provided, and should be used, depending upon the conditions in
which the vehicle is mainly operated. After 60,000 miles (96,000 km) or 48 months, continue the periodic
maintenance at the same mileage or time intervals, whichever comes first.
Maintenance For Off-road Driving (4WD only)ELS0012H
After driving the vehicle off-road through sand, mud, or water; more frequent maintenance may be required for
the following items:
Brake pads and rotors
Brake lines and hoses
Rear final drive oil, transmission fluid, and transfer fluid
Steering linkage
Drive shafts
Engine air cleaner filter
In-cabin microfilters
Schedule 1ELS00101
EMISSION CONTROL SYSTEM MAINTENANCE
Abbreviations: R = Replace. I = Inspect. Correct or replace if necessary. [ ]: At the mileage intervals only Schedule 1Follow Periodic Maintenance Schedule 1 if your driving habits frequently includes
one or more of the following driving conditions:

Repeated short trips of less than 5 miles (8 km).

Repeated short trips of less than 10 miles (16 km) with outside temperatures
remaining below freezing.

Operating in hot weather in stop-and-go “rush hour” traffic.

Extensive idling and/or low speed driving for long distances, such as police,
taxi or door-to-door delivery use.

Driving in dusty conditions.

Driving on rough, muddy, or salt spread roads.

Towing a trailer or using a car-top carrier.Emission Control Sys-
tem MaintenanceMA-6
Chassis and Body
MaintenanceMA-6
Schedule 2Follow Periodic Maintenance Schedule 2 if none of the driving conditions shown
in Schedule 1 apply to the driving habits.Emission Control Sys-
tem MaintenanceMA-8Chassis and Body
MaintenanceMA-8
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
Section -
Page or -
Content Title Perform at number of miles,
kilometers or months, which-
ever comes first.Miles x 1,000
(km x 1,000)
Months3.75
(6)
37.50
(12)
611 . 2 5
(18)
915
(24)
1218.75
(30)
1522.5
(36)
1826.25
(42)
2130
(48)
24
Drive belts NOTE (1)MA-12
Air cleaner filter NOTE (2) [R]MA-15
EVAP vapor linesI*MA-19
Fuel linesI*MA-15
Fuel filter NOTE (3)—
Engine coolant NOTE (4)MA-12
Engine oil R R RRRRRRMA-16
Engine oil filter R R RRRRRRMA-16
Spark plugs (double PLATI-
NUM-TIPPED type)Replace every 105,000 miles (169,000 km).MA-17
Intake and exhaust valve
clearance*NOTE (5)EM-52

PERIODIC MAINTENANCE
MA-7
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Revision: August 20072004 QX56
(1) After 60,000 miles (96,000 km) or 48 months, inspect every 15,000 miles (24,000 km) or 12 months. Replace drive belts if damaged.
(2) If operating mainly in dusty conditions, more frequent maintenance may be required.
(3) Maintenance-free item. For service procedures, go to the FL section.
(4) After 60,000 miles (96,000 km) or 48 months, replace every 30,000 miles (48,000 km) or 24 months.
(5) If valve noise increases, inspect valve clearance.
* Maintenance items and intervals with “*” are recommended by NISSAN for reliable vehicle operation. The owner need not perform
such maintenance in order to maintain the emission warranty or manufacturer recall liability. Other maintenance items and intervals are
required.
CHASSIS AND BODY MAINTENANCE
Abbreviations: R = Replace. I = Inspect. Correct or replace if necessary. L = Lubricate. [ ]: At the mileage intervals only. MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
Section -
Page or -
Content Title Perform at number of miles,
kilometers or months, which-
ever comes first.Miles x 1,000
(km x 1,000)
Months33.75
(54)
2737.5
(60)
3041.25
(66)
3345
(72)
3648.75
(78)
3952.5
(84)
4256.25
(90)
4560
(96)
48
Drive belts NOTE (1) I*MA-12
Air cleaner filter NOTE (2) [R]MA-15
EVAP vapor linesI*MA-19
Fuel linesI*MA-15
Fuel filter NOTE (3)—
Engine coolant NOTE (4) R*MA-12
Engine oil R R R R R R R RMA-16
Engine oil filter R R R R R R R RMA-16
Spark plugs (double PLATI-
NUM-TIPPED type)Replace every 105,000 miles (169,000 km).MA-17
Intake and exhaust valve
clearance*NOTE (5)EM-52
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
Section
- Page
or
- Content
Title Perform at number of miles, kilometers or
months, whichever comes first.Miles x
1,000
(km x
1,000)
Months3.75
(6)
37.5
(12)
611 . 2 5
(18)
915
(24)
1218.75
(30)
1522.5
(36)
1826.25
(42)
2130
(48)
24
Brake lines and cables I IMA-27
Brake pads and rotors I I I IMA-28
Automatic transmission fluid NOTE (1) I I MA-21
Transfer fluid and front final drive oil NOTE (1) I IMA-24,
MA-24
Rear final drive oil NOTE (1) I IMA-24,
MA-24
Steering gear, linkage, axle, and suspension
partsIIIIMA-28,
MA-29
Tire Rotation NOTE (2)MA-27
Drive shaft boots and propeller shaft (4WD) I I I IMA-24
Exhaust system I I I IMA-21
In-cabin microfilter R RAT C - 1 4 2

MA-8
PERIODIC MAINTENANCE
Revision: August 20072004 QX56
(1) If towing a trailer, or using a car-top carrier, or driving on rough or muddy roads, change (not just inspect) oil at every 30,000 miles
(48,000 km) or 24 months.
(2) Refer to “Tire rotation” under the “General maintenance” heading earlier in this section.
Schedule 2ELS00102
EMISSION CONTROL SYSTEM MAINTENANCE
Abbreviations: R = Replace. I = Inspect. Correct or replace if necessary. [ ]: At the mileage intervals only
(1) After 60,000 miles (96,000 km) or 48 months, inspect every 15,000 miles (24,000 km) or 12 months. Replace drive belts if damaged.
(2) Maintenance-free item. For service procedures, go to FL section.
(3) After 60,000 miles (96,000 km) or 48 months, replace every 30,000 miles (48,000 km) or 24 months.
(4) If valve noise increases, inspect valve clearance.
* Maintenance items and intervals with “*” are recommended by NISSAN for reliable vehicle operation. The owner need not perform
such maintenance in order to maintain the emission warranty or manufacturer recall liability. Other maintenance items and intervals are
required. MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
Section
- Page
or
- Content
Title Perform at number of miles, kilometers or
months, whichever comes first.Miles x
1,000
(km x
1,000)
Months33.75
(54)
2737.5
(60)
3041.25
(66)
3345
(72)
3648.75
(78)
3952.5
(84)
4256.25
(90)
4560
(96)
48
Brake lines and cables I IMA-27
Brake pads and rotors I I I IMA-28
Automatic transmission fluid NOTE (1) I IMA-21
Transfer fluid and front final drive oil NOTE (1) I IMA-24,
MA-24
Rear final drive oil NOTE (1) I IMA-24,
MA-24
Steering gear, linkage, axle, and suspension
partsII IIMA-28,
MA-29
Tire Rotation NOTE (2)MA-27
Drive shaft boots and propeller shaft (4WD) I I I IMA-24
Exhaust system I I I IMA-21
In-cabin microfilter R RAT C - 1 4 2
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
Section - Page
or - Content
Title Perform at number of miles,
kilometers or months, whichever
comes first.Miles x 1,000
(km x 1,000)
Months7.5
(12)
615
(24)
1222.5
(36)
1830
(48)
2437.5
(60)
3045
(72)
3652.5
(84)
4260
(96)
48
Drive belts NOTE (1) I*MA-12
Air cleaner filter [R] [R]MA-15
EVAP vapor lines I* I*MA-19
Fuel lines I* I*MA-15
Fuel filter NOTE (2)—
Engine coolant NOTE (3) R*MA-12
Engine oil R R R R R R R RMA-16
Engine oil filter R R R R R R R RMA-16
Spark plugs (PLATINUM-
TIPPED type)Replace every 105,000 miles (169,000 km).MA-17
Intake and exhaust valve clear-
ance*NOTE (4)EM-52