2007 INFINITI QX56 spark plugs replace

EC-82
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
TROUBLE DIAGNOSIS
Trouble Diagnosis IntroductionINFOID:0000000003531617
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 the Work Flow on "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 "Worksheet Sample" 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.
WORK FLOW
MEF036D
SEF233G
SEF234G

EC-328
< SERVICE INFORMATION >
DTC P0300 - P0308 MULTIPLE CYLINDER MISFIRE, NO. 1 - 8 CYLINDER MIS-
FIRE
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm
between the edge of the spark plug and grounded metal portion
as shown in the figure.
11. Crank engine for about 3 seconds, and check whether spark is
generated between the spark plug and the grounded metal por-
tion.
CAUTION:
• Do not approach to the spark plug and the ignition coil
within 50cm. Be careful not to get an electrical shock
while checking, because the electrical discharge voltage
becomes 20kV or more.
• It might cause to damage the ignition coil if the gap of more than 17 mm is taken.
NOTE:
When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.
OK or NG
OK >> GO TO 9.
NG >> GO TO 6.
6.CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a known-good spark plug.
3. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and
the grounded metal portion.
OK or NG
OK >> GO TO 7.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-626
.
7.CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.
OK or NG
OK >> Replace malfunctioning spark plug(s) with standard type
one(s). For spark plug type, refer to EM-29
.
NG >> 1. Repair or clean spark plug.
2. GO TO 8.
8.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and
the grounded portion.
OK or NG
OK >>INSPECTION END
NG >> Replace malfunctioning spark plug(s) with standard type one(s). For spark plug type, refer to EM-
29, "Removal and Installation".
9.CHECK COMPRESSION PRESSURESpark should be generated.
PBIB2325E
Spark should be generated.
SEF156I
Spark should be generated.

DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-353
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Check the initial spark plug for fouling, etc.
OK or NG
OK >> Replace malfunctioning spark plug(s) with standard type
one(s). For spark plug type, refer to EM-29, "
Removal
and Installation".
NG >> 1. Repair or clean spark plug.
2. GO TO 9.
9.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about three seconds, and recheck whether spark is generated between the spark plug
and the grounded portion.
OK or NG
OK >>INSPECTION END
NG >> Replace malfunctioning spark plug(s) with standard type one(s). For spark plug type, refer to EM-
29, "Removal and Installation".
10.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly.
Refer to EM-31
.
Keep fuel hose and all fuel injectors connected to fuel injector gallery.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.
Make sure fuel does not drip from fuel injector.
OK or NG
OK (Does not drip.)>>GO TO 11.
NG (Drips.)>>Replace the fuel injector(s) from which fuel is dripping.
11 .CHECK INTERMITTENT INCIDENT
Refer to EC-138
.
Trouble is fixed.>>INSPECTION END
Trouble is not fixed.>>Replace three way catalyst assembly.
SEF156I
Spark should be generated.

CYLINDER HEAD
EM-69
< SERVICE INFORMATION >
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8. Install the valve collet using Tool.
CAUTION:
When working, take care not to damage valve lifter holes.
9. Install the valve lifters.
• Install the removed parts in their original locations.
• If installing new lifters, select the correct size lifter for proper valve clearance. Refer to EM-56, "
Va l v e
Clearance".
10. Install the spark plug tube if necessary, following the procedure below.
a. Remove any old liquid gasket adhering to the cylinder-head spark plug tube hole.
b. Apply liquid gasket to area within approximately 12 mm (0.47 in) from the edge of the spark plug tube
press-fit side.
Use Genuine RTV Silicone Sealant or equivalent. Refer to GI-45, "
Recommended Chemical Prod-
uct and Sealant".
c. Press-fit the spark plug tube to the specified height “H” using
suitable tool.
CAUTION:
• When press-fitting, take care not to deform the spark plug
tube.
• After press-fitting, wipe off any liquid gasket protruding
onto the cylinder-head upper face.
11. Install the spark plugs.
Inspection After DisassemblyINFOID:0000000003531543
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 the cylinder head for distortion in
six directions as shown, using suitable tools.
• If measurement exceeds the limit, replace the cylinder head.
VALVE DIMENSIONS
Tool number : KV10116200 (J-26336-A)
: KV10115900 (J-26336-20)
: KV10109220 ( — )
WBIA0578E
Standard press-fit height “H” :38.4 - 39.4 mm
(1.512 - 1.551 in)
KBIA1248E
Standard : 0.03 mm (0.0012 in)
Limit : 0.1mm (0.004 in)
PBIC0075E

MA-6
< SERVICE INFORMATION >
PERIODIC MAINTENANCE
PERIODIC MAINTENANCE
Introduction of Periodic MaintenanceINFOID:0000000003533860
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)INFOID:0000000003533861
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 1INFOID:0000000003533862
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 re-
maining 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, kilo-
meters or months, whichever
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 R R R R R RMA-16
Engine oil filter R R R R R R R RMA-16
Spark plugs (double PLATINUM-
TIPPED type)Replace every 105,000 miles (169,000 km).EM-29
Intake and exhaust valve clear-
ance*NOTE (5)EM-103

PERIODIC MAINTENANCE
MA-7
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(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, kilo-
meters 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
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 PLATINUM-
TIPPED type)Replace every 105,000 miles (169,000 km).EM-29
Intake and exhaust valve clear-
ance*NOTE (5)EM-103
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-27
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
Steering gear and linkage, axle and suspension
partsII I IMA-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 RMA-20

MA-8
< SERVICE INFORMATION >
PERIODIC MAINTENANCE
(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 2INFOID:0000000003533863
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.
CHASSIS AND BODY MAINTENANCE
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-27
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
Steering gear and linkage, axle and suspen-
sion 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 RMA-20
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
Section - Page
or - Content Ti-
tle 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).EM-29
Intake and exhaust valve clearance* NOTE (4)EM-103