2003 FORD MUSTANG engine

PINPOINT TEST C: ACCESSORY DRIVE BEARING HOOT
PINPOINT TEST D: POWER STEERING MOAN
PINPOINT TEST E: ENGINE DRIVEN COOLING FAN MOAN operating correctly?
No
INSTALL a new valve lifter/lash adjuster
(s). TEST the system for normal
operation.
Test Step Result / Action to Take
C1 CHECK THE IDLER AND TENSIONER
PULLEY BEARINGS z
Carry out the Vehicle Cold Soak
Procedure in this section.
z Key in START position.
z Place an EngineEAR probe directly on the
pulley center post or bolt to verify which
bearing is making the noise.
z Key in OFF position.
z Is either bearing making the noise? Yes
INSTALL a new pulley/idler. CARRY OUT the
Vehicle Cold Soak Procedure and TEST the
system for normal operation.
No
CONDUCT a diagnosis on other suspect
accessory drive components.
Test Step Result / Action to Take
D1 CHECK THE POWER STEERING
SYSTEM z
Carry out the Vehicle Cold Soak
Procedure in this section.
z Key in START position.
z Turn the steering wheel while the noise
is occurring and listen for changes in
sound pitch or loudness.
z Key in OFF position.
z Does the sound pitch or loudness
change while turning the steering
wheel? Yes
GO to
D2 .
No
CONDUCT a diagnosis on other suspect
accessory drive components. D2 VERIFY THE SOURCE
z
Key in START position.
z Place an EngineEAR probe near the
power steering pump/reservoir while the
noise is occurring. While an assistant
turns the steering wheel, listen for
changes in sound pitch or loudness.
z Key in OFF position.
z Does the sound pitch or loudness
change while turning the steering
wheel? Yes
VERIFY that the supply tube to the pump is
unobstructed. CHECK the fluid condition and
level. DRAIN the fluid and REFILL. CARRY
OUT the Vehicle Cold Soak Procedure and
TEST the system for normal operation. REFER
to Section 211
- 02 .
No
Normal system operation. Test Step Result / Action to Take
E1 CHECK THE ENGINE DRIVEN COOLING
FAN AFTER A COLD SOAK Klj . 51 ba
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PINPOINT TEST F: DRUMMING NOISE z
Carry out the Vehicle Cold Soak Procedure
in this section.
z Key in START position.
z Assess the airflow.
z Raise the engine speed to 1500 rpm while
listening for the moan to increase in
proportion to the airflow.
z Key in OFF position.
z Does the moan increase in proportion to
the airflow? Yes
TEST the fan for normal operation. If the
fan tests normal, GO to
E2 . Otherwise,
REPAIR as necessary.
No
Normal system operation. E2 CHECK THE ENGINE DRIVEN COOLING
FAN AT NORMAL OPERATING TEMPERATURE z
Key in START position.
z Run the engine to normal operating
temperature while listening for the moan to
stop.
z Key in OFF position.
z Does the moan stop? Yes
Normal clutch operation.
No
INSTALL a new fan clutch. TEST the
system for normal operation.
Test Step Result / Action to Take
F1 CHECK THE EXHAUST SYSTEM
z
Key in START position.
z Increase the engine rpm until the noise is the loudest. Note
the engine rpm.
z Key in OFF position.
z Add approximately 9 kg (20 lb) of weight to the exhaust
system. First place the weight at the tail pipe and test, then
at the front pipe.
z Key in START position.
z Increase the engine rpm and listen for the drumming noise.
Note the engine rpm if the noise occurs.
z Key in OFF position.
z Using a vibration analyzer (VA), determine the amount of
vibration that occurs with the drumming noise.
z Is the noise/vibration reduced or eliminated, or does the
noise/vibration occur at a different rpm? Yes
CARRY OUT
Exhaust System Neutralizing in this
section. TEST the system
for normal operation.
No
GO to F2 .
F2 POWERTRAIN/DRIVETRAIN MOUNT NEUTRALIZING
z
Carry out Powertrain/Drivetrain Mount Neutralizing in this
section. Test the system for normal operation.
z Is the noise reduced or eliminated? Yes
Vehicle OK. TEST the
system for normal
operation.
No Klj . 52 ba
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PINPOINT TEST G: ENGINE TICKING, KNOCKING OR CONTINUOUS
RATTLE
PINPOINT TEST H: FRONT SUSPENSION NOISE CONDUCT diagnosis of
other suspect components.
Test Step Result / Action to Take
G1 CHECK FOR NOISE AT THE VALVE COVERS
AND THE FRONT COVERS (OHC ENGINES) z
Carry out the Vehicle Cold Soak Procedure in
this section.
z Key in START position.
z NOTE: For a short- duration ticking noise,
multiple engine starts may be necessary.
z Using an EngineEAR, listen closely at the valve
covers and the front covers (OHC engines) by
placing the probe near the surface of the valve
cover and then on the surface front cover.
z Key in OFF position.
z Is the noise source apparent? Yes
REMOVE the appropriate cover and
INSPECT for loose, worn/broken
components. REPAIR as necessary.
TEST the system for normal operation.
No
GO to
G2 .
G2 CHECK FOR NOISE AT THE CYLINDER
BLOCK z
Key in START position.
z Using an EngineEAR, listen closely at the
cylinder block by placing a probe on or near
each freeze plug.
z Key in OFF position.
z Is the noise source apparent? Yes
REPAIR or INSTALL new components
as necessary.
No
GO to
G3 .
G3 CHECK FOR NOISE WHILE DISCONNECTING
EACH FUEL INJECTOR ELECTRICAL
CONNECTOR, ONE AT A TIME z
Key in START position.
z Disconnect each fuel injector electrical
connector, one at a time, to decrease piston
force and listen for the noise.
z Key in OFF position.
z Is the noise reduced or eliminated? Yes
INSTALL a new fuel injector. TEST the
system for normal operation.
No
INSPECT accessory drive system or the
transmission as a possible source.
Test Step Result / Action to Take
H1 ROAD TEST THE VEHICLE
z
Test drive the vehicle.
z NOTE: An assistant will be needed for this road test.
z During the road test, drive the vehicle over a rough road.
Using ChassisEARs, determine from which
area/component the noise is originating.
z Is there a squeak, creak or rattle noise? Yes
GO to
H2 .
No
The suspension system is
OK. CONDUCT a diagnosis
on other suspect systems. H2 INSPECT THE STEERING SYSTEM
Yes Klj . 53 ba
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Take
J1 ROAD TEST THE VEHICLE
z
NOTE: Wheel or tire vibrations felt in the steering wheel are most
likely related to the front wheel or tire. Vibration felt through the
seat are most likely related to the rear wheel or tire. This may not
always be true, but it can help to isolate the problem to the front
or rear of the vehicle.
z Test drive the vehicle at different speed ranges.
z During the road test, if the vibration can be eliminated by placing
the vehicle in neutral or is affected by the speed of the engine,
the cause is not the wheels or tires.
z Is there a vibration and noise? Yes
GO to
J2 .
No
The wheel and tires
are OK. CONDUCT a
diagnosis on other
suspect systems. J2 CHECK THE FRONT WHEEL BEARINGS
z
Check the front wheel bearings. Refer to Wheel Bearing Check in
this section.
z Are the wheel bearings OK? Yes
GO to
J3 .
No
INSPECT the wheel
bearings. ADJUST or
REPAIR as necessary.
TEST the system for
normal operation. J3 INSPECT THE TIRES
z
Check the tires for missing weights.
z Check the wheels for damage.
z Inspect the tire wear pattern. Refer to the Tire Wear Patterns
chart in this section.
z Do the tires have an abnormal wear pattern? Yes
CORRECT the
condition that caused
the abnormal wear.
INSTALL new tire(s).
TEST the system for
normal operation.
No
GO to
J4 .
J4 TIRE ROTATION
z
Spin the tires slowly and watch for signs of lateral runout.
z Spin the tires slowly and watch for signs of radial runout. Yes
GO to
J5 .
No
CHECK the wheel and
tire balance.
CORRECT as
necessary. TEST the
system for normal
operation. Klj . 56 ba
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PINPOINT TEST L: CLUTCH VIBRATION appropriate workshop manual for the service procedures.
z Secure the brake drums (if so equipped), by installing wheel
hub bolt nuts, reversed.
z Carefully accelerate the drivetrain while checking for vibration.
z Is the vibration present? assemblies as necessary.
TEST the system for
normal operation.
Test Step Result / Action to Take
L1 CHECK ENGINE COMPONENTS FOR GROUNDING
z
NOTE: Make sure the clutch is the cause of the
vibration concern. The vibration should occur during
clutch operation. The clutch can also be difficult to
engage or disengage. Eliminate all related systems
before checking the clutch components.
z NOTE: Check the driveline angles and driveshaft
runout before disassembling the clutch system. Refer
to Section 205 - 00 for the correct driveline angle
specifications.
z Check the powertrain/drivetrain mounts, exhaust
manifolds or other engine components for grounding
on the chassis.
z Are any mounts or engine components
grounded? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
L2 .
L2 CHECK THE ACCESSORY DRIVE
z
Remove the accessory drive belt.
z Does the vibration stop with the accessory drive
belt removed? Yes
DIAGNOSE the accessory drive
components.
No
GO to
L3 .
L3 CHECK FOR LOOSE CLUTCH PRESSURE PLATE
BOLTS z
Check for loose clutch pressure plate bolts. Inspect
the clutch pressure plate for damage or for material
between the pressure plate and flywheel.
z Are there any loose bolts or damage? Yes
TIGHTEN the bolts to
specifications or if damaged,
INSTALL a new clutch pressure
plate. REFER to
Section 308 - 01 .
TEST the system for normal
operation.
No
GO to L4 .
L4 CHECK THE CLUTCH DISC SPRINGS
z
Check for worn, broken or loose clutch disc springs.
z Are the clutch springs worn, broken or loose? Yes
INSTALL a new clutch disc.
REFER to
Section 308 - 01 . TEST
the system for normal operation.
No
GO to L5 .
L5 CHECK THE CLUTCH DISC SPLINES
z
Inspect the clutch disc splines for damage or wear.
z Is there damage or wear? Yes
INSTALL a new clutch disc.
REFER to
Section 308 - 01 . TEST Klj . 61 ba
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4. While the noise is occurring, either place an EngineEAR probe near the IAC valve and the inlet
tube, or create a 6.35 mm (0.25 in)- 12.7 mm (0.50 in) air gap between the inlet tube and the
clean air tube. If the IAC valve is making the noise, install a new IAC valve.
5. Test the vehicle for normal operation.
Steering Gear Grunt/Shudder Test
1. Start and run the vehicle to operating temperature.
2. Set engine idle speed to 1200 rpm.
3. CAUTION: Do not hold the steering wheel against the stops for more than three to
five seconds at a time. Damage to the power steering pump will occur.
Rotate the steering wheel to the RH stop, then turn the steering wheel 90° back from that
position. Turn the steering wheel slowly in a 15° to 30° arc.
4. Turn the steering wheel another 90°. Turn the steering wheel slowly in a 15° to 30° arc.
5. Repeat the test with power steering fluid at different temperatures.
6. If a light grunt is heard or a low (50- 200 Hz) shudder is present, this is a normal steering system
condition.
7. If a loud grunt is heard, or a strong shudder is felt, fill and purge the power steering system.
Checking Tooth Contact Pattern and Condition of the Ring and Pinion
There are two basic types of conditions that will produce ring and pinion noise. The first type is a howl
or chuckle produced by broken, cracked, chipped, scored or forcibly damaged gear teeth and is
usually quite audible over the entire speed range. The second type of ring and pinion noise pertains to
the mesh pattern of the gear pattern. This gear noise can be recognized as it produces a cycling pitch
or whine. Ring and pinion noise tends to peak in a narrow speed range or ranges, and will tend to
remain constant in pitch.
1. Raise and support the vehicle. For additional information, refer to Section 100 - 02 .
2. Drain the axle lubricant. Refer to Section 205 - 02A for Ford 7.5 rear axles or
Section 205 - 02B for
Ford 8.8 integral axles.
3. Remove the carrier assembly or the axle housing cover depending on the axle type. Refer to Section 205 - 02A for Ford 7.5 rear axles or
Section 205 - 02B for Ford 8.8 integral axles.
4. Inspect the gear set for scoring or damage. Klj . 64 ba
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Wheel and tire NVH concerns are directly related to vehicle speed and are not generally affected by
acceleration, coasting or decelerating. Also, out-of-
balance wheel and tires can vibrate at more than
one speed. A vibration that is affected by the engine rpm, or is eliminated by placing the transmission
in NEUTRAL is not related to the tire and wheel. As a general rule, tire and wheel vibrations felt in the
steering wheel are related to the front tire and wheel assemblies. Vibrations felt in the seat or floor are
related to the rear tire and wheel assemblies. This can initially isolate a concern to the front or rear.
Careful attention must be paid to the tire and wheels. There are several symptoms that can be caused
by damaged or worn tire and wheels. Carry out a careful visual inspection of the tires and wheel
assemblies. Spin the tires slowly and watch for signs of lateral or radial runout. Refer to the tire wear
chart to determine the tire wear conditions and actions. Klj . 68 ba
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GENERAL PROCEDURES
Exhaust System Neutralizing
WARNING: Exhaust gases contain carbon monoxide, which is harmful to health and
potentially lethal. Repair exhaust system leaks immediately. Never operate the engine in an
enclosed area.
WARNING: Exhaust system components are hot.
NOTE: Neutralize the exhaust system to relieve strain on mounts which can be sufficiently bound up to
transmit vibration as if grounded.
1. WARNING: The electrical power to the air suspension system must be shut off prior
to hoisting, jacking or towing an air suspension vehicle. This can be accomplished by
turning off the air suspension switch. Failure to do so can result in unexpected inflation
or deflation of the air springs, which can result in shifting of the vehicle during these
operations.
CAUTION: Make sure the system is warmed up to normal operating temperature, as
thermal expansion can be the cause of a strain problem.
Raise and support the vehicle.
2. Loosen all exhaust hanger attachments and reposition the hangers until they hang free and straight.
3. Loosen all exhaust flange joints.
4. Place a stand to support the muffler parallel to the vehicle frame with the muffler pipe bracket free of stress.
5. Tighten the muffler connection.
6. Tighten all the exhaust hanger clamps and flanges (tighten the exhaust manifold flange joint last).
zVerify there is adequate clearance to prevent grounding at any point in the system. Make
sure that the catalytic converter and heat shield do not contact the frame rails.
z After neutralization, the rubber in the exhaust hangers should show some flexibility when
movement is applied to the exhaust system.
z With the exhaust system installed securely and cooled, the rear hanger should be angled
forward.
7. Lower the vehicle.
8. Test the exhaust system for normal operation.
SECTION 100-
04: Noise, Vibration and Harshness 2003 Mustang Workshop Manual Klj . 1 ba
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