Nissan Xterra. Manual - part 346

EM-12

< SYSTEM DESCRIPTION >

[VQ40DE]

NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING

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 

driving

Top of en-
gine
Rocker 
cover
Cylinder 
head

Ticking or 
clicking

C

A

—

A

B

—

Tappet 
noise

Valve clearance

EM-18

Rattle

C

A

—

A

B

C

Camshaft 
bearing 
noise

Camshaft runout
Camshaft journal oil 
clearance

EM-76
EM-76

Crank-
shaft pul-
ley
Cylinder 
block 
(Side of 
engine)
Oil pan

Slap or 
knock

—

A

—

B

B

—

Piston pin 
noise

Piston to piston pin oil 
clearance
Connecting rod bushing 
oil clearance

EM-112

 

EM-112

Slap or 
rap

A

—

—

B

B

A

Piston 
slap noise

Piston to cylinder bore 
clearance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend 
and torsion

EM-112
EM-112
EM-112
EM-112

Knock

A

B

C

B

B

B

Connect-
ing rod 
bearing 
noise

Connecting rod bushing 
oil clearance
Connecting rod bearing 
oil clearance

EM-112
EM-112

Knock

A

B

—

A

B

C

Main bear-
ing noise

Main bearing oil clear-
ance
Crankshaft runout

EM-112
EM-112

Front of 
engine
Timing 
chain case

Tapping or 
ticking

A

A

—

B

B

B

Timing 
chain and 
chain ten-
sioner 
noise

Timing chain cracks 
and wear
Timing chain tensioner 
operation

EM-59
EM-67

Front of 
engine

Squeak-
ing or fizz-
ing

A

B

—

B

—

C

Drive belts 
(Sticking 
or slip-
ping)

Drive belts deflection

EM-13

Creaking

A

B

A

B

A

B

Drive belts 
(Slipping)

Idler pulley bearing op-
eration

Squall
Creak

A

B

—

B

A

B

Water 
pump 
noise

Water pump operation

CO-21

Rattle

—

—

A

—

—

—

VTC

VTC lock pin clearance

EM-76

DRIVE BELTS

EM-13

< PERIODIC MAINTENANCE >

[VQ40DE]

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PERIODIC MAINTENANCE

DRIVE BELTS

Exploded View

INFOID:0000000009484439

Checking Drive Belts

INFOID:0000000009484440

WARNING:

Be sure to perform when the engine is stopped.
1. Remove air duct and resonator assembly when inspecting drive belt. Refer to 

EM-24, "Removal and

Installation"

.

2. Make sure that the drive belt auto-tensioner indicator is within

the allowable working range (A) as shown.

3. Visually check entire belt for wear, damage or cracks.
4. If the indicator is out of allowable working range or drive belt is

damaged, replace the drive belt. Refer to 

EM-13, "Removal and

Installation"

.

Adjustment

INFOID:0000000009484441

There is no manual drive belt tension adjustment. The drive belt tension is automatically adjusted by the drive

belt auto-tensioner.

Removal and Installation

INFOID:0000000009484442

REMOVAL

1. Remove air duct and resonator assembly. Refer to 

EM-24, "Removal and Installation"

.

LBIA0427E

1.

Drive belt

2.

Power steering oil pump pulley

3.

Generator pulley

4.

Crankshaft pulley

5.

A/C compressor

6.

Cooling fan pulley

7.

Idler pulley

8.

Drive belt auto-tensioner

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EM-14

< PERIODIC MAINTENANCE >

[VQ40DE]

DRIVE BELTS

2. Rotate the drive belt auto-tensioner in the direction of arrow

(loosening direction of tensioner) as shown, using suitable tool.

WARNING:

Avoid placing hand in a location where pinching may occur

if the tool accidentally comes off.

3. Remove the drive belt. 

INSTALLATION

Installation is in the reverse order of removal.

CAUTION:

Make sure belt is securely installed around all pulleys.

Drive Belt Auto-Tensioner and Idler Pulley

INFOID:0000000009484443

REMOVAL

1. Remove drive belt. Refer to 

EM-13, "Removal and Installation"

.

2. Remove drive belt auto-tensioner and idler pulley.

INSTALLATION

Installation is in the reverse order of removal.

CAUTION:

If there is damage greater than peeled paint, replace drive belt auto-tensioner.

LBIA0428E

1.

Idler pulley

2.

Drive belt auto-tensioner

AWBIA0861GB

AIR CLEANER FILTER

EM-15

< PERIODIC MAINTENANCE >

[VQ40DE]

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AIR CLEANER FILTER

Exploded View

INFOID:0000000009484444

Removal and Installation

INFOID:0000000009484445

REMOVAL

1. Remove the engine room cover (if equipped).
2. Disconnect air duct and resonator from the air cleaner case (upper).
3. Disconnect mass air flow sensor.
4. Unhook clips, and lift air cleaner case (upper).
5. Remove air cleaner filter.

INSTALLATION

Installation is in the reverse order of removal.

1.

Air cleaner case (lower)

2.

Air cleaner filter

3.

Air cleaner case (upper)

4.

Mass air flow sensor

5.

Air duct and resonator

Front

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