Nissan Altima L32. Instruction — part 619

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NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING

FUNCTION DIAGNOSIS

NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING

NVH Troubleshooting - Engine Noise

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WBIA0069E

NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING

EM-13

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Use the Chart Below to Help You Find the Cause of the Symptom

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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

driving

Top of en-
gine
Rocker
cover
Cylinder
head

Ticking or
clicking

C

A

—

A

B

—

Tappet
noise

Valve clearance

EM-49

Rattle

C

A

—

A

B

C

Camshaft
bearing
noise

Camshaft journal clear-
ance
Camshaft runout

EM-41
EM-41

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

Slap or
knock

—

A

—

B

B

—

Piston pin
noise

Piston and piston pin
clearance
Connecting rod bushing
clearance

EM-83
EM-83

Slap or
rap

A

—

—

B

B

A

Piston
slap noise

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

EM-83
EM-83
EM-83
EM-83

Knock

A

B

C

B

B

B

Connect-
ing rod
bearing
noise

Connecting rod bushing
clearance (Small end)
Connecting rod bearing
clearance (Big end)

EM-83
EM-83

Knock

A

B

—

A

B

C

Main bear-
ing noise

Main bearing oil clear-
ance
Crankshaft runout

EM-83
EM-83

Front of
engine
Timing
chain cov-
er

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-52

Front of
engine

Squeak-
ing or fizz-
ing

A

B

—

B

—

B

Drive belts
(Sticking
or slip-
ping)

Drive belts deflection

EM-16

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-19

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< ON-VEHICLE MAINTENANCE >

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SPARK PLUG

ON-VEHICLE MAINTENANCE

SPARK PLUG

Removal and Installation

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REMOVAL

1. Remove the ignition coil. Refer to

EM-35, "Removal and Installation"

.

2. Remove the spark plug with a suitable spark plug wrench.

INSPECTION AFTER REMOVAL

• Do not use a wire brush for cleaning the spark plugs. Replace as

necessary.

• If plug is covered with carbon, a spark plug cleaner may be used.

1.

Ignition coil

2.

Spark plug

3.

Rocker cover

AWBIA0208GB

PBIC2982E

SMA773C

Cleaner air pressure : less than 588 kPa (6 kg/cm

2

, 85 psi)

Cleaning time

: less than 20 seconds

SPARK PLUG

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• Checking and adjusting plug gap is not required between change

intervals. If the gap is out of specification, replace the spark plug.

INSTALLATION

Installation is in the reverse order of removal.

Gap (nominal)

: 1.1 mm (0.043 in)

SMA806CA

Temperature range

NGK

Standard type

DILKAR6A-11

Gap (nominal)

1.1 mm (0.043 in)