check engine FORD MUSTANG 2003 User Guide

components as necessary.
z Broken
powertrain
mounts. z
INSPECT the powertrain
mounts. INSTALL new
mounts as necessary.
REFER to Section 303 - 01A
for 3.8L engines or
Section 303 - 01B for 4.6L (2V)
engines.
z Idle speed too
high. z
CHECK for the correct idle
speed.
z Driveline clunk—
occurs as the vehicle
starts to move
forward following a
stop z
Worn or galled
driveshaft slip-
yoke splines. z
CLEAN and INSPECT the
splines of the yoke for a
worn or galled condition.
INSTALL a new yoke as
necessary. REFER to
Section 205 - 01 .
z Worn or galled
driveshaft and
coupling shaft
splines. z
CLEAN and INSPECT the
splines of the driveshaft and
coupling shaft for a worn or
galled condition. INSTALL a
new driveshaft assembly as
necessary. REFER to
Section 205 - 01 .
z Loose rear leaf
spring U- bolts. z
CHECK the U- bolts for
loose nuts. TIGHTEN to
specification. REFER to
Section 204 - 02 .
z Driveline clunk (FWD
vehicles)—occurs
during acceleration or
from cruise to
coast/deceleration z
Damaged or
worn inboard
constant velocity
(CV) joint. z
INSPECT the inboard CV
joint and boot. REPAIR or
INSTALL a new CV joint as
necessary.
z Driveline clunk (4WD
vehicles)—occurs
during shift- on-the- fly
engagement z
Clutch relay.
z Shift motor.
z Transfer case.
z GEM. z
CHECK the 4WD
engagement system.
REPAIR or INSTALL new
components as necessary.
z Clicking, popping or
grinding— occurs
while vehicle is
turning z
Inadequate or
contaminated
lubrication in the
(CV) joints. z
CHECK the CV boots and
joints for wear or damage.
REPAIR or INSTALL new
components as necessary.
z Another
component
contacting the
halfshaft. z
CHECK the halfshafts and
the area around the
halfshafts. REPAIR as
necessary.
z Brake
components. z
INSPECT the front brakes
for wear or damage.
REPAIR as necessary.
REFER to Section 206 - 03 .
z Steering
components. z
INSPECT the drag link,
inner and outer tie- rods or
idler arm for wear or
damage. REPAIR as
necessary. REFER to
Section 211 - 02 .
z Suspension
components. z
INSPECT the upper and
lower ball joints for wear or
damage. REPAIR as
necessary. REFER to Klj . 19 ba
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CARRY OUT a driveline
vibration test. REFER to
Section 205
- 00 . REPAIR as
necessary.
z Binding or
damaged
splines on the
driveshaft slip-
yoke. z
CLEAN and INSPECT the
splines of the slip- yoke,
driveshaft and coupling
shaft for wear or damage.
INSTALL a new slip- yoke or
driveshaft assembly as
necessary. REFER to
Section 205 - 01 . REPAIR as
necessary.
z Driveshaft
runout. z
CARRY OUT a Runout
Check. REFER to Section 205 - 00 . REPAIR as
necessary.
z Incorrect lateral
and radial
tire/wheel
runout. z
INSPECT the tire and
wheels. MEASURE tire
runouts. REPAIR or
INSTALL new components
as necessary. REFER to
Section 204 - 04 .
z Driveline angles
out of
specification. z
CHECK for correct driveline
angles. REPAIR as
necessary. REFER to
Section 205 - 00 .
z Incorrectly
seated CV joint
in the front
wheel hub. z
CHECK the outer CV joint
for correct seating into the
hub. REPAIR as necessary. Symptom Chart —
Engine Noise/Vibration Condition
Possible Sources Action
z Grinding noise—
occurs during
engine cranking z
Incorrect starter
motor mounting. z
INSPECT the starter motor
for correct mounting.
REPAIR as necessary.
REFER to Section 303 - 06 .
z Starter motor. zCHECK the starter motor.
REPAIR or INSTALL a new
starter motor as necessary.
REFER to Section 303 - 06 .
z Incorrect starter
motor drive
engagement. z
INSPECT the starter motor
drive and flexplate/flywheel
for wear or damage.
INSTALL a new starter
motor drive or flywheel as
necessary. REFER to
Section 303 - 06 .
z Engine ticking
noise z
Fuel injector.
z Fuel line.
z Oil pump.
z Valve lifter.
z Belt tensioner.
z Water pump.
z Obstruction of cooling
fan. z
Go To Pinpoint Test B .
z Engine drumming zPowertrain mount. zCARRY OUT Klj . 23 ba
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noise—
normally
accompanied by
vibration Powertrain/Drivetrain Mount Neutralizing in this
section.
z Damaged or
misaligned exhaust
system. z
INSPECT the exhaust
system for loose or broken
clamps and brackets.
CARRY OUT Exhaust System Neutralizing in this
section.
z Whistling noise—
normally
accompanied
with poor idle
condition z
Air intake system. zCHECK the air intake
ducts, air cleaner, throttle
body and vacuum hoses for
leaks and correct fit.
REPAIR or ADJUST as
necessary. REFER to
Section 303 - 12
z
Clunking noise zWater pump has
excessive end play or
imbalance. z
CHECK the water pump for
excessive end play.
INSPECT the water pump
with the drive belt off for
imbalance. INSTALL a new
water pump as necessary.
REFER to Section 303 -
03A .
z Generator has
excessive end play. z
CHECK the generator for
excessive end play.
REPAIR or INSTALL a new
generator. REFER to
Section 414 - 02 .
z Pinging noise zExhaust system leak. zINSPECT the exhaust
system for leaks. REPAIR
as necessary.
z Gasoline octane too
low. z
VERIFY with customer the
type of gasoline used.
CORRECT as necessary.
z Knock sensor
operation. z
CHECK the knock sensor.
INSTALL a new knock
sensor as necessary.
REFER to Section 303 - 14 .
z Incorrect spark
timing. z
CHECK the spark timing.
REPAIR as necessary.
z High operating
temperature. z
INSPECT cooling system
for leaks. 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.
z Foul- out spark plug. zCHECK the spark plugs.
REPAIR or INSTALL new
spark plugs as necessary.
z Catalytic converter. zAcceptable noise.
z Knocking noise—
light knocking
noise, also z
Excessive clearance
between the piston
and the cylinder wall. z
Engine cold and at high
idle. Using an EngineEAR,
pull a spark plug or fuel Klj . 24 ba
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described as
piston slap. Noise
is most
noticeable when
engine is cold
with light to
medium
acceleration.
Noise disappears
as engine warms
injector connector until the
noise goes away. CARRY
OUT a cylinder bore
clearance to piston check.
INSTALL a new piston.
REFER to
Section 303 - 01A
for 3.8L engines or
Section 303 - 01B for 4.6L (2V)
engines.
z Knocking noise—
light double
knock or sharp
rap sound.
Occurs mostly
with warm engine
at idle or low
speeds in DRIVE.
Increases in
relation to engine
load. Associated
with poor
lubrication history z
Excessive clearance
between the piston
and the piston pin. z
INSTALL a new piston or
piston pin. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Knocking noise—
light knocking
noise is most
noticeable when
engine is warm.
Noise tends to
decrease when
vehicle is
coasting or in
neutral z
Excessive clearance
between the
connecting rod
bearings and the
crankshaft. z
Engine warm and at idle.
Using an EngineEAR,
PULL a spark plug or fuel
injector connector until the
noise goes away. INSTALL
new bearings. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Knocking— deep
knocking noise.
Noise is most
noticeable when
engine is warm,
at lower rpm and
under a light load
and then at float z
Worn or damaged
crankshaft main
bearings. z
CARRY OUT DERU test.
CHECK for noise with
vehicle at operating
temperature, during
medium to heavy
acceleration. CHECK at
idle with injector
disconnected, noise does
not change. INSTALL new
main bearings. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Knocking noise—
occurs mostly
with warm engine
at light/medium
acceleration z
Spark plugs. zCHECK the spark plug for
damage or wear. INSTALL
new spark plugs as
necessary.
z Carbon accumulation
in combustion
chamber. z
REMOVE carbon from
combustion chamber.
z Whine or
moaning noise z
Air intake system. zCHECK the air cleaner and
ducts for correct fit.
INSPECT the air intake
system for leaks or
damage. REPAIR as
necessary. Klj . 25 ba
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z
Generator electrical
field or bearings. z
CARRY OUT generator
load test. REPAIR or
INSTALL a new generator
as necessary. REFER to
Section 414 - 02 .
z Drone type noise zExhaust system. zCARRY OUT the Exhaust System Neutralizing in this
section. REPAIR as
necessary.
z A/C compressor. zCHECK for noise with
vehicle at constant speeds.
CYCLE the compressor on
and off and listen for a
change in pitch. REPAIR as
necessary. REFER to
Section 412 - 03 .
z Powertrain mounts. zCARRY OUT the
Powertrain/Drivetrain Mount Neutralizing in this
section.
z Sputter type
noise— noise
worse when cold,
lessens or
disappears when
vehicle is at
operating
temperature z
Damaged or worn
exhaust system
components. z
INSPECT the exhaust
system for leaks or
damage. REPAIR as
necessary. REFER to
Section 309 - 00 .
z Rattling noise—
noise from the
upper engine
(valve train).
Worse when
engine is cold z
Low oil level. zCHECK oil level. FILL as
necessary.
z Thin or diluted oil. zINSPECT the oil for
contamination. If oil is
contaminated, CHECK for
the source. REPAIR as
necessary. CHANGE the oil
and filter.
z Low oil pressure. zCARRY OUT an oil
pressure test. If not within
specifications, REPAIR as
necessary. REFER to
Section 303 - 00 .
z Worn rocker
arms/fulcrums or
followers. z
CARRY OUT a valve train
analysis. INSTALL new
valve train components as
necessary. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Worn valve guides. zCARRY OUT a valve train
analysis. INSTALL new
valve guides as necessary.
REFER to Section 303 - 01A
for 3.8L engines or
Section 303 - 01B for 4.6L (2V)
engines. Klj . 26 ba
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z
Excessive runout of
valve seats on the
valve face. z
CARRY OUT a valve seat
runout test. INSPECT the
valve face and seat.
INSTALL new valves as
necessary. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Rattling noise—
from the bottom
of the vehicle z
Loose muffler shields
or catalytic converter
shields. z
CHECK the exhaust
system for loose exhaust
shields. REPAIR as
necessary.
z Thumping
noise— from the
bottom of the
vehicle, worse at
acceleration z
Exhaust pipe/muffler
grounded to chassis. z
CHECK the exhaust
system to chassis
clearance. CHECK the
exhaust system hangers for
damage. REPAIR as
necessary. REFER to
Section 309 - 00 .
z Whoosh— occurs
during light
vehicle
acceleration.
Heard inside the
vehicle z
Throttling late,
creating turbulence
transmitted through
the plastic manifold. z
CHECK for leaks or
missing seal in the dash
panel.
z Engine
vibration—
increases
intensity as
engine rpm is
increased z
Engine out-of-
balance. z
CARRY OUT Neutral
Engine Run- Up (NERU)
Test. ROTATE the torque
converter, 120° for 3 bolt
and 180° for 4 bolt.
INSPECT the torque
converter pilot outer
diameter to crankshaft pilot
inner diameter. REPAIR as
necessary. REFER to
Section 307 - 01 .
z Engine
vibration— is felt
with increases
and decreases in
engine rpm z
Strain on exhaust
mounts. z
CARRY OUT the Exhaust
System Neutralizing
procedure in this section.
REPAIR as necessary.
z Damaged or worn
powertrain/drivetrain
mounts. z
CHECK the
powertrain/drivetrain
mounts for damage.
REPAIR as necessary.
z Engine or
transmission
grounded to chassis. z
INSPECT the
powertrain/drivetrain for
correct clearances.
REPAIR as necessary.
z Engine
vibration—
vibration felt at all
times z
Excessive engine
pulley runout. z
CARRY OUT Engine
Accessory Test. INSTALL a
new engine pulley as
necessary. REFER to
Section 303 - 01A for 3.8L
engines or Section 303 - 01B
for 4.6L (2V) engines.
z Damaged or worn
accessory
component. z
CARRY OUT Engine
Accessory Test. REPAIR or
INSTALL a new component Klj . 27 ba
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as necessary.
z Accelerator pedal
vibration— felt
through the pedal
as a buzz z
Throttle cable loose
or misrouted. z
INSPECT the throttle cable.
REPAIR as necessary.
REFER to Section 310 - 02 .
z Engine
vibration— mostly
at coast/neutral
coast. Condition
improves with
vehicle
accelerating z
Combustion
instability. z
CHECK the ignition system.
INSTALL new components
as necessary.
z Engine vibration
or shudder—
occurs with light
to medium
acceleration
above 56 km/h
(35 mph) z
Worn or damaged
spark plugs. z
INSPECT the spark plugs
for cracks, high resistance
or broken insulator.
INSTALL a new spark plug
(s) as necessary.
z Plugged fuel injector. zREPAIR or INSTALL a new
injector as necessary.
REFER to Section 303 - 04A
for 3.8L engines or
Section 303 - 04B for 4.6L (2V)
engines.
z Damaged spark plug
wire. z
INSPECT the spark plug
wires for damage. INSTALL
a new spark plug wire(s) as
necessary.
z Contaminated fuel. zINSPECT the fuel for
contamination. DRAIN the
fuel system and refill.
z Worn or damaged
torque converter. z
CHECK the torque
converter. INSTALL a new
torque converter as
necessary. REFER to
Section 307 - 01 .
Symptom Chart—
Idle Noise/Vibration Condition
Possible Sources Action
z Idle air control (IAC)
valve moan — occurs
on throttle tip- out z
IAC valve is
contaminated
with oil. z
GO to Component Tests in
this section.
z Accessory drive belt
chirp — occurs at idle
or high idle, cold or
hot. Most common
occurrence is during
humid weather z
Accessory drive
belt worn, or
pulley is
misaligned or
loose. z
INSPECT for loose or
misaligned pulleys. CHECK
the drive belt for wear or
damage. INSTALL new
pulley(s)/drive belt, or
accessory drive components
as necessary. REFER to
Section 303 - 05 .
z Accessory drive
bearing hoot —
occurs at idle or high
idle in cold
temperatures of
approximately +4°C z
Accessory drive
idler or
tensioner pulley
bearing is
experiencing
stick/slip z
Go To Pinpoint Test C . Klj . 28 ba
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port. DISCARD the leaking
parts, and INSTALL a new
component.
z Vehicles with a
plastic intake
manifold. z
Acceptable condition. Some
plastic manifolds exhibit this
noise, which is the effect of
the plastic manifold.
z Automatic
transmission buzz or
hiss z
Incorrect
driveline
angles. z
CHECK for correct driveline
angles. REPAIR as
necessary. REFER to
Section 205 - 00 .
z Worn or
damaged main
control
solenoids or
valves. z
Using a transmission tester,
activate the solenoids to
duplicate sound. INSTALL
new components as
necessary. REFER to
Section 307 - 01 .
z Manual Transmission
Clutch throw- out
bearing whine. A
change in noise pitch
or loudness while
depressing the clutch
pedal z
Worn throw- out
bearing. z
INSTALL a new throw- out
bearing. REFER to Section 308 - 01 .
z Heating, vacuum and
air conditioning
(HVAC) system chirp
— most audible inside
the vehicle. Listen for
a change in noise
pitch or loudness
while changing the
HVAC system blower
speed z
Damaged or
worn HVAC
blower bearing. z
INSTALL a new blower
motor. REFER to Section 412 - 02 .
z Air conditioning (A/C)
clutch ticking —
occurs when the
compressor clutch
engages z
Acceptable
noise.
z Incorrect air
gap. z
LISTEN to the clutch to
determine if the noise occurs
with clutch engagement. A
small amount of noise is
acceptable. If the noise is
excessive, CHECK the A/C
clutch air gap. INSPECT the
A/C clutch for wear or
damage. INSTALL a new
clutch as necessary. REFER
to Section 412 - 03 .
z Intermittent rattle, or
scraping/rubbing
noise z
Loose exhaust
heat shield(s). z
INSPECT the exhaust
system for loose parts using
a glove or clamps to verify
cause. REPAIR as
necessary. REFER to
Section 309 - 00 .
z Wiring, hose or
other part
interfering with
accessory drive
belt or pulley. z
INSPECT accessory drive
system closely verifying
there is adequate clearance
to all rotating components.
REPAIR as necessary.
z Engine ticking or
knocking noise —
occurs during idle or z
Piston noise or
valvetrain noise
(bled down z
Go To Pinpoint Test G . Klj . 30 ba
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high idle during the
first cold start of the
day
lifter/lash
adjuster).
z A continuous, speed-
dependent rattle from
the engine — occurs
during idle or high idle
during the first cold
start of the day and
disappears as the
engine warms up z
Piston noise or
valvetrain noise
(bled down
lifter/lash
adjuster). z
Go To Pinpoint Test G .
z Idle vibration—a low-
frequency vibration (5-
20 Hz) or mild shake
that is felt through the
seat/floorpan z
Cylinder misfire. zUsing a scan tool, CHECK
the ignition system. CARRY
OUT a cylinder power test.
REFER to Section 303 - 00 .
z Engine or
torque
converter out of
balance. z
VERIFY the torque
converter to crankshaft pilot
clearance is correct,
REPAIR as necessary. RE-
INDEX the torque converter
on the flex plate by 120° on
a 3 bolt converter or 180° for
a 4 bolt converter. REFER to
Section 307 - 01 . RETEST
the vehicle.
z Idle vibration—a high-
frequency vibration
(20–80 Hz) or buzz,
that is felt through the
steering wheel or seat z
Exhaust system
mounts bound
up. z
VERIFY concern occurs at
engine firing frequency.
CHECK that the exhaust
system vibrates at the same
frequency as the engine.
ADD 9– 14 km (20–30 lb.) to
the tail pipe to test, CARRY
OUT Exhaust System Neutralizing in this section.
z Body mounts
loose. z
INSPECT the body mounts.
REPAIR as necessary.
z Power steering
lines grounded
out. z
INSPECT that the power
steering lines are not
contacting the chassis or
each other. REPAIR as
necessary. Symptom Chart—
Squeak and Rattle Condition
Possible Sources Action
z Squeak— heard
inside the vehicle
when
closing/opening
the door z
Insufficient
lubrication on
the door hinge
or check strap. z
LUBRICATE the hinge or check
strap.
z Internal door
components
loose, rubbing or
misaligned. z
CHECK the inside of the door.
TIGHTEN or ALIGN as
necessary. USE the Rotunda
Squeak and Rattle Kit to isolate
any rubbing components.
z Squeak— heard
inside the vehicle
when z
Worn or
damaged glass
run/channel. z
REPAIR or INSTALL a new
glass run/channel. REFER to
Section 501 - 11 . Klj . 31 ba
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Symptom Chart—
Transmission (Manual) and Transfer Case Noise/Vibration Condition
Possible Sources Action
z Clutch rattling noise—
occurs with clutch
engaged, noise
changes/disappears
with clutch pedal
depressed z
Flywheel bolts,
clutch housing bolts
or clutch pressure
plate bolts loose. z
TIGHTEN the bolts to
specifications. CHECK
the bolts for damage.
z Clutch squeaking
noise— noise is heard
when the clutch is
operated. Vehicle
moves slowly or
creeps when the clutch
is disengaged. Can
also be difficult to shift
into first and reverse
gear z
Pilot bearing seized
or damaged. z
INSTALL a new pilot
bearing. REFER to
Section 308 - 01 .
z Clutch squeaking
noise— occurs with
clutch pedal
depressed/released z
Worn clutch pedal
shaft or bushings. z
INSPECT the clutch
pedal for wear or
damage. REPAIR as
necessary. REFER to
Section 308 - 02 .
z Clutch whirring/rattle
noise— occurs when
clutch pedal is
depressed z
Worn, damaged or
misaligned clutch
release bearing. z
INSTALL a new clutch
release bearing.
REFER to Section 308 -
01 .
z Clutch grating/grinding
noise— occurs when
clutch pedal is
depressed z
Clutch pressure
plate fingers bent or
worn. z
INSPECT the clutch
pressure plate release
fingers. INSTALL a new
pressure plate as
necessary. REFER to
Section 308 - 01 .
z Contact surface of
clutch release
bearing worn or
damaged. z
INSTALL a new clutch
release bearing.
REFER to Section 308 -
01 .
z Clutch chatter— a
small amount of noise
when clutch pedal is
released at initial take-
off z
Clutch engagement. zAcceptable operating
condition.
z Clutch chatter/grabs—
in some cases a
shudder is felt. Occurs
with clutch pedal
depressed/released z
Damaged or worn
powertrain/driveline
mounts. z
INSPECT the
powertrain/drivetrain
mounts. INSTALL new
mounts as necessary.
REFER to Section 303 -
01A for 3.8L engines or
Section 303 - 01B for
4.6L (2V) engines.
z Binding or dragging
plunger of the clutch
master cylinder or
slave cylinder. z
CHECK the master and
slave cylinder
operation. INSPECT
the components for
damage or wear.
INSTALL a new master
or slave cylinder as
necessary. REFER to Klj . 40 ba
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