2005 INFINITI QX4 check engine

EM-40Revision: October 2005
TIMING CHAIN
2005 QX56
3. Install the crankshaft sprockets for both banks.

Install each crankshaft sprocket so that its flange side (the
larger diameter side without teeth) faces in the direction
shown.
NOTE:
The same parts are used but facing directions are different.
4. Install the timing chains and associated parts.

Align the mating mark on each sprocket and the timing chain for installation.
CAUTION:

Before installing chain tensioner, it is possible to change the position of mating mark on tim-
ing chain and each sprocket. After the mating marks are aligned, keep them aligned by hold-
ing them by hand.

Install the slack guides and tension guides onto the correct side by checking the identification mark on
the surface.

Install the chain tensioner with the plunger locked in with the stopper pin.
CAUTION:

Before and after the installation of the chain tensioner, make sure that the mating mark on the
timing chain is not out of alignment.

After installing the chain tensioner, remove the stopper pin to release the tensioner. Make
sure the tensioner is released.

To avoid chain-link skipping of the timing chain, do not move crankshaft or camshafts until
the front cover is installed.
5. In the same way as for the right bank, install the timing chain and associated parts on the left side.
6. Install the oil pump.
7. Install the oil pump drive spacer as follows:

Install so that the front mark on the front edge of the oil pump
drive spacer faces the front of the engine.

Insert the oil pump drive spacer according to the directions of
the crankshaft key and the two flat surfaces of the oil pump
inner rotor.

If the positional relationship does not allow the insertion,
rotate the oil pump inner rotor to allow the oil pump drive
spacer to be inserted.
8. Install the front oil seal using suitable tool.
CAUTION:
Do not scratch or make burrs on the circumference of the
oil seal.
KBIA2515E
KBIA2490E
PBIC0059E

EM-42Revision: October 2005
TIMING CHAIN
2005 QX56
b. Install the bolts in the numerical order shown.
12. Install the crankshaft pulley.

Install the key of the crankshaft.

Insert the pulley by lightly tapping it.
CAUTION:
Do not tap pulley on the side surface where the belt is installed (outer circumference).
13. Tighten the crankshaft pulley bolt.

Lock the crankshaft using suitable tool, then tighten the bolt.

Perform the following steps for angular tightening:
a. Apply engine oil onto the threaded parts of the bolt and seating area.
b. Select the one most visible notch of the four on the bolt flange.
Corresponding to the selected notch, put a mating mark (such
as paint) on the crankshaft pulley.
14. Rotate the crankshaft pulley in normal direction (clockwise when
viewed from engine front) to check for parts interference.
15. Installation of the remaining components is in the reverse order
of removal.
WBIA0468E
Crankshaft pulley bolt torque
Step 1 : 93.1 N·m (9.5 kg-m, 69 ft-lb)
Step 2 : additional 90° (angle tightening)
KBIA2519E

CAMSHAFT
EM-51
C
D
E
F
G
H
I
J
K
L
MA
EM
Revision: October 20052005 QX56
5. Install the camshaft sprockets using the following procedure:
a. Install the camshaft sprockets aligning them with the matching
marks painted on the timing chain when removed. Align the
camshaft sprocket key groove with the dowel pin on the cam-
shaft front edge at the same time. Then temporarily tighten
bolts.

Install the intake and exhaust side camshaft sprockets by
selectively using the groove of the dowel pin according to the
bank. (Common part used for both banks.)
b. Lock the hexagonal part of the camshaft in the same way as for
removal, and tighten the bolts.
c. Check again that the timing mating mark on the timing chain and
on each sprocket are aligned.
6. Install the chain tensioner using the following procedure:
NOTE:
Left bank is shown.
a. Install the chain tensioner.

Compress the plunger and hold it using a stopper pin when
installing.

Loosen the slack guide side timing chain by rotating the cam-
shaft hexagonal part if mounting space is small.
b. Remove the stopper pin and release the plunger, and then apply
tension to the timing chain.
c. Install the chain tensioner cover onto the front cover (RH bank).

Apply liquid gasket as shown.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-45, "
Recommended Chemical Products and Sealants"
.
7. Check and adjust valve clearances. Refer to EM-51, "
Va l v e
Clearance" .
8. Installation of the remaining components is in the reverse order
of removal.
Valv e C le aranceEBS00LMA
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, battery cover and air duct assembly. Refer to EM-11, "
Removal and Installa-
tion" , SC-9, "REMOVAL" and EM-14, "Removal and Installation" .
KBIA2482E
KBIA2480E
Chain tensioner bolts : 6.9 N·m (0.70 kg-m, 61 in-lb)
Tensioner cover bolts : 9.0 N·m (0.92 kg-m, 80 in-lb)KBIA2479E
KBIA2547E

EM-54Revision: October 2005
CAMSHAFT
2005 QX56

The specified valve lifter thickness is the dimension at normal temperatures. Ignore dimensional differ-
ences caused by temperature. Use the specifications for hot engine condition to adjust.
1. Remove the camshaft. Refer to EM-43, "
Removal and Installation" .
2. Remove the valve lifters at the locations that are out of specification.
3. Measure the center thickness of the removed valve lifters using
suitable tool.
4. Use the equation below to calculate the valve lifter thickness for replacement.

Valve lifter thickness calculation:
Thickness of replacement valve lifter = t1+ (C1 - C2)
t1 = Thickness of removed valve lifter
C1 = Measured valve clearance
C2= Standard valve clearance:

Thickness of a new valve lifter can be identified by stamp
marks on the reverse side (inside the cylinder).
Stamp mark N788 indicates 7.88 mm (0.3102 in) in thickness.

Available thickness of valve lifter: 25 sizes with range 7.88 to
8.36 mm (0.3102 to 0.3291 in) in steps of 0.02 mm (0.0008 in)
(when manufactured at factory). Refer to EM-101, "
Available
Valve Lifter" .
5. Install the selected valve lifter.
6. Install the camshaft.
7. Manually turn the crankshaft pulley a few turns.
8. Make sure the valve clearances for cold engine are within specifications by referring to the specified val-
ues.
9. After completing the repair, check the valve clearances again with the specifications for a warmed engine.
Make sure the values are within specifications.
KBIA0057E
Intake : 0.36 mm (0.0142 in)*
Exhaust : 0.37 mm (0.0146 in)*
*: Approximately 80°C (176°F)
KBIA0 119 E
Valve clearance standard:
Hot*
Intake : 0.304 - 0.416 mm (0.012 - 0.016 in)
Exhaust : 0.308 - 0.432 mm (0.012 - 0.017 in)
Cold
Intake : 0.26 - 0.34 mm (0.010 - 0.013 in)
Exhaust : 0.29 - 0.37 mm (0.011 - 0.015 in)
* : Approximately 80°C (176°F)

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

EM-60Revision: October 2005
CYLINDER HEAD
2005 QX56
INSPECTION AFTER REMOVAL
Cylinder Head Bolts Diameter

Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between d1 and d2
exceeds the limit, replace the bolt with a new one.

If reduction of diameter appears in a position other than d2, use
it as d2 point.
INSTALLATION
1. Install a new cylinder head gasket.
2. Install the cylinder head. Follow the steps below to tighten the
bolts in the numerical order shown.
CAUTION:

If cylinder head bolts are re-used, check their diameters
before installation. Refer to EM-60, "
Cylinder Head Bolts
Diameter" .
a. Apply engine oil to threads and seating surface of the bolts.
b. Measure the tightening angle using Tool.
CAUTION:
Measure the tightening angle using Tool. Do not measure
visually.
3. Installation of the remaining components is in the reverse order of removal.Limit (d1 - d2) : 0.18 mm (0.0071 in)
KBIA0189E
Step a : 98.1 N·m (10 kg-m, 72 ft-lb)
Step b :Loosen in the reverse order of tightening.
Step c : 44.1 N·m (4.5 kg-m, 33 ft-lb)
PBIC0068E
Tool number : KV10112100 (BT-8653-A)
Step d : 60° clockwise
Step e : 60° clockwise
WBIA0603E

EM-70Revision: October 2005
ENGINE ASSEMBLY
2005 QX56
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 EM-14, "
REMOVAL" .
8. Disconnect the vacuum hose between the vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-12, "
REMOVAL" .
10. Remove the drive belts. Refer to EM-12, "
Removal" .
11. Remove the fan blade. Refer to CO-15, "
REMOVAL" .
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-26, "
REMOVAL" .
18. Remove the A/C compressor bolts and set the compressor aside. Refer to ATC-179, "
REMOVAL" .
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-29, "
REMOVAL" .
22. Disconnect the heater hoses at 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 (4x4 only). Refer to FFD-11, "
REMOVAL" .
25. Remove the exhaust manifolds. Refer to EM-19, "
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-244, "
Removal and Installation
(4x2)" or AT-247, "Removal and Installation (4x4)" .
28. Lift using 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.

Loosen the bolts diagonally.
WBIA0464E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
PBIC1556E

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 —