PRECAUTIONSEI-3
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PRECAUTIONSPFP:00001
Service NoticeEIS004W7
When removing or installing various parts, place a cloth or padding on the vehicle body to prevent
scratches.
Handle trim, molding, instruments, grille, etc. carefully during removing or installing. Be careful not to soil
or damage them.
Apply sealing compound where necessary when installing parts.
When applying sealing compound, be careful that the sealing compound does not protrude from parts.
When replacing any metal parts (for example body outer panel, members, etc.), be sure to take rust pre-
vention measures.
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EIS004W8
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.
WARNING:
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.
EM-1
ENGINE MECHANICAL
B ENGINE
CONTENTS
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SECTION
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PRECAUTIONS .....................................................
..... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 3
Precautions for Drain Engine Coolant ................. ..... 3
Precautions for Disconnecting Fuel Piping ......... ..... 3
Precautions for Removal and Disassembly ........ ..... 3
Precautions for Inspection, Repair and Replace-
ment .................................................................... ..... 3
Precautions for Assembly and Installation .......... ..... 3
Parts Requiring Angular Tightening .................... ..... 4
Precautions for Liquid Gasket ............................. ..... 4
REMOVAL OF LIQUID GASKET SEALING ..... ..... 4
LIQUID GASKET APPLICATION PROCEDURE ..... 4
PREPARATION ...................................................... ..... 6
Special Service Tools .......................................... ..... 6
Commercial Service Tools ................................... ..... 8
NOISE, VIBRATION, AND HARSHNESS (NVH)
TROUBLESHOOTING ........................................... ... 10
NVH Troubleshooting —Engine Noise ................ ... 10
Use the Chart Below to Help You Find the Cause
of the Symptom. .................................................. .... 11
ENGINE ROOM COVER ....................................... ... 12
Removal and Installation ..................................... ... 12
REMOVAL ........................................................ ... 12
INSTALLATION ................................................ ... 12
DRIVE BELTS ........................................................ ... 13
Checking Drive Belts ........................................... ... 13
DRIVE BELT TENSION ................................... ... 13
Removal and Installation ..................................... ... 13
REMOVAL ........................................................ ... 13
INSTALLATION ................................................ ... 14
Drive Belt Auto Tensioner and Idler Pulley .......... ... 14
REMOVAL ........................................................ ... 14
INSTALLATION ................................................ ... 14
AIR CLEANER AND AIR DUCT ............................ ... 15
Removal and Installation ..................................... ... 15
REMOVAL ........................................................ ... 15INSTALLATION ................................................
... 15
Removal and Installation (Viscous paper type) ... ... 16
REMOVAL ........................................................ ... 16
INSTALLATION ................................................ ... 16
INTAKE MANIFOLD .............................................. ... 17
Removal and Installation ..................................... ... 17
REMOVAL ........................................................ ... 17
INSTALLATION ................................................ ... 19
INSPECTION AFTER INSTALLATION ............. ... 20
EXHAUST MANIFOLD AND THREE WAY CATA-
LYST ....................................................................... ... 21
Removal and Installation ..................................... ... 21
REMOVAL ........................................................ ... 21
INSPECTION AFTER REMOVAL .................... ... 22
INSTALLATION ................................................ ... 22
OIL PAN AND OIL STRAINER .............................. ... 24
Removal and Installation ..................................... ... 24
REMOVAL ........................................................ ... 24
INSPECTION AFTER REMOVAL .................... ... 25
INSTALLATION ................................................ ... 26
INSPECTION AFTER INSTALLATION ............. ... 27
IGNITION COIL ...................................................... ... 28
Removal and Installation ..................................... ... 28
REMOVAL ........................................................ ... 28
INSTALLATION ................................................ ... 28
SPARK PLUG (PLATINUM-TIPPED TYPE) .......... ... 29
Removal and Installation ..................................... ... 29
REMOVAL ........................................................ ... 29
INSPECTION AFTER REMOVAL .................... ... 29
INSTALLATION ................................................ ... 30
FUEL INJECTOR AND FUEL TUBE ..................... ... 31
Removal and Installation ..................................... ... 31
REMOVAL ........................................................ ... 31
INSTALLATION ................................................ ... 32
INSPECTION AFTER INSTALLATION ............. ... 34
ROCKER COVER .................................................. ... 35
Removal and Installation ..................................... ... 35
REMOVAL ........................................................ ... 35
INSTALLATION ................................................ ... 36
PRECAUTIONSEM-3
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PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EBS00REI
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.
WARNING:
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 Drain Engine CoolantEBS00REJ
Drain engine coolant when engine is cooled.
Precautions for Disconnecting Fuel PipingEBS00REK
Before starting work, make sure no fire or spark producing items are in the work area.
Release fuel pressure before disconnecting and disassembly.
After disconnecting pipes, plug openings to stop fuel leakage.
Precautions for Removal and DisassemblyEBS00REL
When instructed to use special service tools, use the specified tools. Always be careful to work safely,
avoid forceful or uninstructed operations.
Exercise maximum care to avoid damage to mating or sliding surfaces.
Cover openings of engine system with tape or the equivalent, if necessary, to seal out foreign materials.
Mark and arrange disassembly parts in an organized way for easy troubleshooting and assembly.
When loosening nuts and bolts, as a basic rule, start with the one furthest outside, then the one diagonally
opposite, and so on. If the order of loosening is specified, do exactly as specified. Power tools may be
used where noted in the step.
Precautions for Inspection, Repair and ReplacementEBS00REM
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precautions for Assembly and InstallationEBS00REN
Use torque wrench to tighten bolts or nuts to specification.
When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with the
ones in center, then ones on inside and outside diagonally in this order. If the order of tightening is speci-
fied, do exactly as specified.
Replace with new gasket, packing, oil seal or O-ring.
Thoroughly wash, clean, and air-blow each part. Carefully check engine oil or engine coolant passages for
any restriction and blockage.
Avoid damaging sliding or mating surfaces. Completely remove foreign materials such as cloth lint or dust.
Before assembly, oil sliding surfaces well.
Release air within route when refilling after draining engine coolant.
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTINGEM-11
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Use the Chart Below to Help You Find the Cause of the Symptom.EBS00RET
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
A: Closely related B: Related C: Sometimes related—: Not related
Location of
noise Type of
noise Operating condition of engine
Source of noise Check item Refer-
ence page
Before
warm- up After
warm- up When
start- ing When
idling When
racing While
driv- ing
Top of
engine
Rocker
cover
Cylinder
head Ticking or
clicking
CA
—AB —Tappet noise Valve clearance EM-69
Rattle C A—ABC Camshaft
bearing noiseCamshaft journal clear-
ance
Camshaft runout EM-50EM-50
Crankshaft
pulley
Cylinder
block (Side
of engine)
Oil panSlap or
knock
—
A— BB —Piston pin
noise Piston and piston pin
clearance
Connecting rod bush-
ing clearance EM-95
EM-97
Slap or
rap
A
—— BBA Piston slap
noisePiston-to-bore clear-
ance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsion EM-99EM-95
EM-95
EM-96
Knock A B C B B B
Connecting
rod bearing
noiseConnecting rod bush-
ing oil clearance (Small
end)
Connecting rod bear-
ing clearance (Big end)
EM-97EM-96
Knock A B
—ABC Main bearing
noiseMain bearing oil clear-
ance
Crankshaft runout EM-101EM-100
Front of
engine
Chain case
cover
Front coverTapping
or ticking
AA
—BBB Timing chain
and chain
tensioner
noiseTiming chain cracks
and wear
Timing chain tensioner
operation
EM-40
EM-37
Front of
engineSqueak-
ing or
fizzing
AB
—B— CDrive belts
(Sticking or
slipping) Drive belts deflection
EM-13
Creaking A B A B A B Drive belts
(Slipping)Idler pulley bearing
operation
Squall
Creaking AB
—BAB Water pump
noiseWater pump operation CO-19,
"INSPEC-
TION
AFTER
REMOVA
L"
SPARK PLUG (PLATINUM-TIPPED TYPE)EM-29
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SPARK PLUG (PLATINUM-TIPPED TYPE)PFP:22401
Removal and InstallationEBS00RF4
REMOVAL
1. Remove the ignition coil. Refer to EM-28, "REMOVAL" .
2. Remove the spark plug using suitable tool.
INSPECTION AFTER REMOVAL
Do not use a wire brush for cleaning.
If the spark plug tip is covered with carbon, a spark plug cleaner may be used.
1. Ignition coil 2. Spark plug
KBIA2505E
SEM294A
SMA773C
Cleaner air pressure
: Less than 588 kPa (5.9 bar, 6 kg/cm2 , 85 psi)
Cleaning time : Less than 20 seconds
ENGINE ASSEMBLYEM-75
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4. Remove the engine hood. Refer to BL-13, "Removal and Installation of Hood Assembly" .
5. Remove the cowl extension. Refer to EI-18, "
Removal and Installation" .
6. Remove the engine room cover using power tools.
7. Remove the air duct and air cleaner case assembly. Refer to EM-15, "
Removal and Installation" .
8. Disconnect the vacuum hose between the vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-14, "
Removal and Installation" .
10. Remove the drive belts. Refer to EM-13, "
Removal and Installation" .
11. Remove the fan blade. Refer to CO-17, "
Removal and Installation (Crankshaft Driven Type)" .
12. Disconnect the engine room harness from the fuse box and set it aside.
13. Disconnect the ECM.
14. Disconnect the engine room harness from the engine side and set it aside.
15. Disconnect the engine harness grounds.
16. Disconnect the power steering reservoir tank from the engine and move it aside.
17. Disconnect the power steering oil pump from the engine. Move it aside and secure it using suitable wire or rope. Refer to PS-21, "
Removal and Installation" .
18. Remove the A/C compressor bolts and set the compressor aside. Refer to ATC-175, "
Removal and Instal-
lation for Compressor" (ATC).
19. Disconnect the brake booster vacuum line.
20. Disconnect the EVAP line.
21. Disconnect the fuel hose at the engine side connection. Refer to EM-31, "
Removal and Installation" .
22. Disconnect the heater hoses at the 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 front final drive assembly (4WD only). Refer to FFD-12, "
Removal and Installation" .
25. Remove the exhaust manifolds. Refer to EM-21, "
Removal and Installation" .
26. Install the engine slingers into the left bank cylinder head and right bank cylinder head.
27. Remove the A/T. Refer to AT- 2 4 3 , "
Removal and Installation
(2WD)" or AT- 2 4 6 , "Removal and Installation (4WD)" .
28. Lift using a hoist and secure the engine in position.
29. Remove the engine assembly from the vehicle, avoid interfer- ence with the vehicle body.
CAUTION:
Before and during lifting, always check if any harnesses
are left connected.
30. Remove the parts that may restrict installation of the engine to the engine stand.
NOTE:
This procedure is described assuming that you use an engine stand mounting to the surface to which the
transmission mounts.
a. Remove the drive plate.
Holding the crankshaft pulley bolt, lock the crankshaft to remove the drive plate bolts.
WBIA0464E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
WBIA0715E
CYLINDER BLOCKEM-79
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* Refer to GI-46, "Recommended Chemical Products and Sealants" .
DISASSEMBLY
NOTE:
Explained here is how to disassemble with engine stand supporting transmission surface. When using differ-
ent type of engine stand, some steps may be different.
1. Remove engine assembly and mount to engine stand. Refer to EM-74, "
Removal and Installation" .
CAUTION:
Before removing the hanging chains, make sure engine stand is stable and there is no risk of over-
turning.
2. Drain engine oil. Refer to LU-8, "
Changing Engine Oil" .
3. Drain engine coolant by removing the cylinder block drain plugs “A”, “B ”, “C” and “D ” as shown.
4. Remove the following components and associated parts (the parts referred to in step 1 are not included here).
Oil pan (upper and lower) and oil strainer. Refer to EM-24, "Removal and Installation" .
Crankshaft pulley, front cover and timing chain. Refer to EM-37, "Removal and Installation" .
Camshaft. Refer to EM-46, "Removal and Installation" .
Cylinder head. Refer to EM-64, "Removal and Installation" .
5. Remove knock sensor and sub harness.
CAUTION:
Carefully handle sensor, avoiding shocks.
6. Check connecting rod side clearance. Refer to EM-94, "
CONNECTING ROD SIDE CLEARANCE" .
7. Remove piston and connecting rod assembly as follows.
a. Position the crankshaft pin corresponding to the connecting rod to be removed onto bottom dead center.
1. Knock sensor sub-harness 2. Knock sensor 3. Cylinder block
4. Main bearing upper 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 lower 17. Main bearing lower 18. Crankshaft
19. Pilot converter 20. Thrust bearing upper 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
WBIA0419E
KBIA2549E
EM-82Revision: November 2009
CYLINDER BLOCK
2006 QX56
18. Remove pilot converter using Tool if necessary.
ASSEMBLY
1. Fully air-blow the coolant and oil passages in the cylinder block, cylinder bore, and crankcase to removeany foreign material.
CAUTION:
Use goggles to protect your eyes.
2. Install each plug to the cylinder block (only screw-type plugs are shown).
Apply liquid gasket.
Use Genuine Thread Sealant or equivalent. Refer to GI-
46, "Recommended Chemical Products and Sealants".
Replace copper washers with new ones.
Tighten each plug as specified below.
3. Install main bearings and thrust bearings.
a. Remove any dust, dirt, and oil on the bearing mating surfaces of the cylinder block and main bearing caps.
b. Install thrust bearings to both sides of the No. 3 journal housing on the cylinder block and main bearing caps
Install thrust bearings with the oil groove facing the crankshaft
arm (outside).
Install thrust bearings with a protrusion in the center on the
main bearing caps.
c. Install main bearings paying attention to the direction.
Install the one with oil holes onto the cylinder block and the
one without oil holes onto the main bearing cap.
Before installing bearings, apply engine oil to bearing surface
(inside). Do not apply oil to the back surface, but thoroughly
clean it.
When installing, align the bearing stopper to the notch.
Ensure the oil holes on the cylinder block and those on the
corresponding bearing are aligned. Tool number : ST16610001 (J-23907)
WBIA0596E
Part Washer
Tightening torque
A Yes 53.9 N·m (5.5 kg-m, 40 ft-lb)
BNo 19.6 N ·m (2.0 kg-m, 15 ft-lb)
C Yes 62.7 N·m (6.4 kg-m, 46 ft-lb)
D Yes 62.7 N·m (6.4 kg-m, 46 ft-lb)
WBIA0419E
PBIC0093E
PBIC0094E