Ford Falcon. Manual — part 12

100-04-20

Noise, Vibration and Harshness

100-04-20

DIAGNOSIS AND TESTING (Continued)

Condition

Source

Action

Howl—can occur at various speeds

Incorrect ring and pinion contact,

CHECK the ring and pinion and

and driving conditions—affected by

incorrect bearing preload or gear

bearings for damage. INSPECT the
ring and pinion wear pattern. REFER

acceleration and deceleration

damage.

to Checking Tooth Contact Pattern and
Condition of the Ring and Pinion
component test in this section.
ADJUST or INSTALL new components
as necessary. REFER to Section
205-02 .

Chuckle—heard at

Incorrect ring and pinion contact or by

CHECK the ring and pinion for

coast/deceleration—also described as

damaged teeth on the coast side of

damage. INSPECT the ring and pinion
wear pattern. REFER to Checking

a knock

the ring and pinion.

Tooth Contact Pattern and Condition
of the Ring and Pinion component test
in this section. ADJUST or INSTALL
new components as necessary.
REFER to Section 205-02 .

Knock—noise occurs at various

Gear tooth damage to the ring and

CHECK the differential case and ring

speeds—not affected by acceleration

and pinion for damage. INSTALL new

pinion.

components as necessary. REFER to

or deceleration

Section 205-02 .

Excessive axle shaft end play

CHECK the axle end play using a dial

indicator. INSTALL a new axle shaft or

(vehicles with integral axles).

side gears as necessary. REFER to
Section 205-02 .

Scraping noise—a continuous low

CHECK the pinion bearings. INSTALL

Worn or damaged pinion bearings.

new pinion bearings as necessary.

pitched noise starting at low speeds

REFER to Section 205-02 .

Driveline shudder—occurs during

Rear drive axle assembly

CHECK the axle mounts and the rear

suspension for damage or wear.

acceleration from a slow speed or stop

mispositioned.

REPAIR as necessary.

INSPECT the bolts. TIGHTEN the bolt

Loose rear axle bolts.

nuts to specification.

Incorrect or high CV joint operating

CHECK vehicle ride height is within

angle.

limits. REPAIR as necessary.

Damaged or worn front suspension

CHECK for a loose stabilizer bar,

damaged or loose strut/strut bushings

components.

or loose or worn ball joints. INSPECT
the steering linkage for wear or
damage. REPAIR or INSTALL new
components as necessary. REFER to
Section 204-00 .

CHECK for correct driveline angles.

Driveline angles out of specification.

REPAIR as necessary. REFER to
Section 205-00 .

ROTATE the driveshaft and CHECK

U-joints binding or seized.

for rough operation or seized U-joints.
INSTALL new U-joints as necessary.
REFER to Section 205-01 .

INSPECT the driveshaft shaft CV joint

Binding the driveshaft CV joint.

and coupling shaft for a worn, or
damaged condition. INSTALL a new or
driveshaft assembly as necessary.
REPAIR as necessary. REFER to
Section 205-01 . REPAIR as
necessary.

INSPECT the bolts. TIGHTEN the

Loose rear axle bolts.

bolts to specification.

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100-04-21

Noise, Vibration and Harshness

100-04-21

DIAGNOSIS AND TESTING (Continued)

Condition

Source

Action

Driveline vibration—occurs at cruising

CHECK for wear or incorrect seating.

U-joints are worn.

INSTALL new driveshaft as necessary.

speeds

REFER to Section 205-01 .

Worn or damaged driveshaft center

CHECK the insulator for damage or

wear. ROTATE the driveshaft and

bearing support.

CHECK for rough operation. INSTALL
a new center bearing support as
necessary. REFER to Section 205-01 .

INSPECT the axle pinion flange.

Loose axle pinion flange bolts.

TIGHTEN the pinion flange bolts to
specification. REFER to Section
205-01 .

CARRY OUT a Runout Check. REFER

Excessive axle pinion flange runout.

to Section 205-01 . REPAIR as
necessary.

CHECK the driveshaft for damage,

Driveshaft is out-of-balance.

missing balance weights or
undercoating. CHECK driveshaft
balance. CARRY OUT a driveline
vibration test. REFER to Section
205-01 . REPAIR as necessary.

Binding or damaged driveshaft CV

INSPECT the driveshaft CV joint for

wear or damage. INSTALL a new

joint.

driveshaft assembly as necessary.
REFER to Section 205-01 . REPAIR
as necessary.

CARRY OUT a runout check. REFER

Driveshaft runout.

to Section 205-01 . REPAIR as
necessary.

Incorrect lateral and radial tyre/wheel

INSPECT the tyre and wheels.

MEASURE tyre runouts. REPAIR or

runout.

INSTALL new components as
necessary. REFER to Section 204-04 .

CHECK for correct driveline angles.

Driveline angles out of specification.

REPAIR as necessary. REFER to
Section 205-00 .

Incorrectly seated CV joint in the front

CHECK the outer CV joint for correct

seating into the hub. REPAIR as

wheel hub.

necessary. REFER to Section 205-04
for front CV joints or Section 205-05
for rear CV joints.

Symptom Chart — Engine Noise/Vibration

Condition

Source

Action

Grinding noise—occurs during engine

INSPECT the starter motor for correct

Incorrect starter motor mounting.

mounting. REPAIR as necessary.

cranking

REFER to Section 303-06 .

CHECK the starter motor. REPAIR or

Starter motor.

INSTALL a new starter motor as
necessary. REFER to Section 303-06 .

Incorrect starter motor drive

INSPECT the starter motor drive and

flexplate/flywheel for wear or damage.

engagement.

If necessary, INSTALL a new starter
motor drive. REFER to Section 303-06
. If necessary, INSTALL a new
flexplate/flywheel. REFER to Section
303-01a for 2.0L Zetec engine or
Section 303-01b for 3.0L (4V) engine.

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100-04-22

Noise, Vibration and Harshness

100-04-22

DIAGNOSIS AND TESTING (Continued)

Condition

Source

Action

Fuel injector.

Engine ticking noise

Go to PinPoint Test B .

Fuel line.
Oil pump.
Valve lifter.
Belt tensioner.
Water pump.
Obstruction of cooling fan.

Engine drumming noise—normally

CARRY OUT Powertrain/Drivetrain

Powertrain mount.

accompanied by vibration

Mount Neutralizing in this section.

Damaged or misaligned exhaust

INSPECT the exhaust system for

loose or broken clamps and brackets,

system.

flex coupling or damper (2.0L Zetec).
CARRY OUT Exhaust System
Neutralizing in this section.

Whistling noise—normally

CHECK the air intake ducts, air

Air intake system.

cleaner, throttle body and vacuum

accompanied with poor idle condition

hoses for leaks and correct fit.
REPAIR or ADJUST as necessary.
REFER to Section 303-12 .

Water pump has excessive end play or

CHECK the water pump for excessive

Clunking

noise

end play. INSPECT the water pump

imbalance.

with the drive belt off for imbalance.
INSTALL a new water pump as
necessary. REFER to Section 303-03 .

CHECK the generator for excessive

Alternator has excessive end play.

end play. REPAIR or INSTALL a new
alternator. REFER to Section 414-02 .

INSPECT the exhaust system for

Pinging noise

Exhaust system leak.

leaks. REPAIR as necessary.

VERIFY with customer the type of

Gasoline octane too low.

gasoline used. CORRECT as
necessary.

CHECK the knock sensor. INSTALL a

Knock sensor operation.

new knock sensor as necessary.
REFER to Section 303-14 .

CHECK the spark timing. REPAIR as

Incorrect spark timing.

necessary.

INSPECT cooling system for leaks.

High operating temperature.

CHECK the coolant level. REFILL as
necessary. CHECK the coolant for the
correct mix ratio. DRAIN and REFILL
as needed. CHECK engine operating
temperature is within specifications.
REPAIR as necessary.

CHECK the spark plugs. REPAIR or

Foul-out spark plug.

INSTALL new spark plugs as
necessary.

Catalytic converter.

Acceptable noise.

Knocking noise—light knocking noise,

Excessive clearance between the

Engine cold and at high idle. Using an

also described as piston slap—noise is

EngineEAR, pull a spark plug or fuel

piston and the cylinder wall.

most noticeable when engine is cold

injector connector until the noise goes

with light to medium

away. CARRY OUT a cylinder bore

acceleration—noise disappears as

clearance to piston check. INSTALL a

engine warms

new piston.

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100-04-23

Noise, Vibration and Harshness

100-04-23

DIAGNOSIS AND TESTING (Continued)

Condition

Source

Action

Knocking noise—light double knock or

Excessive clearance between the

INSTALL a new piston or piston pin.

sharp rap sound—occurs mostly with

piston and the piston pin.

warm engine at idle or low speeds in
DRIVE—increases in relation to engine
load—associated with poor lubrication
history

Knocking noise—light knocking noise

Excessive clearance between the

Engine warm and at idle. PULL a

is most noticeable when engine is

connecting rod bearings and the

spark plug or fuel injector connector

warm—noise tends to decrease when

until the noise goes away. INSTALL

crankshaft.

vehicle is coasting or in neutral

new bearings.

Knocking—deep knocking

Worn or damaged crankshaft main

CARRY OUT DERU test. CHECK for

noise—noise is most noticeable when

noise with vehicle at operating

bearings.

engine is warm, at lower rpm and

temperature, during medium to heavy
acceleration. CHECK at idle with

under a light load and then at float

injector disconnected, noise does not
change. INSTALL new main bearings.

Knocking noise—occurs mostly with

CHECK the spark plug for damage or

Spark plugs.

warm engine at light/medium

wear. INSTALL new spark plugs as

acceleration

necessary.

Carbon accumulation in combustion

REMOVE carbon from combustion

chamber.

chamber.

CHECK the air cleaner and ducts for

Whine or moaning noise

Air intake system.

correct fit. INSPECT the air intake
system for leaks or damage. REPAIR
as necessary. REFER to Section
303-12 .

CARRY OUT alternator load test.

Alternator electrical field or bearings.

REPAIR or INSTALL a new alternator
as necessary. REFER to Section
412-02 .

CARRY OUT the Exhaust System

Drone type noise

Exhaust system.

Neutralizing in this section. REPAIR as
necessary.

CHECK for noise with vehicle at

A/C compressor.

constant speeds. CYCLE the
compressor on and off and listen for a
change in pitch. REPAIR as
necessary. REFER to Section 412-03 .

CARRY OUT the Exhaust System

Powertrain mounts.

Neutralizing in this section.

Sputter type noise—noise worse when

Damaged or worn exhaust system

INSPECT the exhaust system for leaks

cold, lessens or disappears when

or damage. REPAIR as necessary.

components.

vehicle is at operating temperature

REFER to Section 309-00 .

Rattling noise—noise from the upper

Low oil level.

CHECK oil level. FILL as necessary.

engine (valve train)—worse when
engine is cold

INSPECT the oil for contamination. If

Thin or diluted oil.

oil is contaminated, CHECK for the
source. REPAIR as necessary.
CHANGE the oil and filter.

CARRY OUT an oil pressure test. If

Low oil pressure.

not within specifications, REPAIR as
necessary. REFER to Section 303-00 .

Worn rocker arms/fulcrums or

CARRY OUT a valve train analysis.

INSTALL new valve train components

followers.

as necessary. REFER to Section 303.

CARRY OUT a valve train analysis.

Worn valve guides.

INSTALL new valve guides as
necessary. REFER to Section 303.

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