Nissan Altima HL32 Hybrid. Manual - part 374

EM-10

< FUNCTION DIAGNOSIS >

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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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AWBIA0047ZZ

1.

Water pump auto tensioner 2. Crankshaft

3.

Idler pulley

4.

Water pump pulley

5. Drive belt

6.

Timing chain

7.

Water pump

8. Rotation mechanism

9.

Valve mechanism 

NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING

EM-11

< FUNCTION DIAGNOSIS >

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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

10. Valve

A. Piston pin noise

B.

Piston pin slap

C.

Main bearing noise

D. Water pump noise

E.

Timing chain and chain tensioner noise

F.

Drive belt noise

G. Connecting rod bearing noise

H.

Camshaft bearing noise

J.

Tappet noise

Location 

of noise

Type of 

noise

Operating condition of Hy-

brid System

Using Consult III

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-48

Rattle

C

A

—

A

B

C

Camshaft 
bearing 
noise

Camshaft journal clear-
ance
Camshaft runout

EM-40
EM-47

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

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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-51

Front of 
engine

Squeak-
ing or fizz-
ing

A

B

—

B

—

B

Drive belts 
(Sticking 
or slip-
ping)

Drive belts deflection

EM-14

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-18

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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-34, "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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< ON-VEHICLE MAINTENANCE >

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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)