steering FORD MUSTANG 2003 User Guide

Lateral runout means measuring the movement or "wobble" of a wheel or tire at the sidewall. Radial
runout means measuring the out-of-
round at the tread surface.
Rustling
Intermittent sound of varying frequency (100- 2000 Hz), sounds similar to shuffling through leaves.
Shake
A low- frequency vibration (5-20 Hz), usually with visible component movement. Usually relates to tires,
wheels, brake drums or brake discs if it is vehicle speed sensitive, or engine if it is engine speed
sensitive. Also referred to as a shimmy or wobble.
Shimmy
An abnormal vibration or wobbling, felt as a side- to-side motion of the steering wheel in the driveshaft
rotation. Also described as waddle.
Shudder
A low- frequency vibration that is felt through the steering wheel or seat during light brake application.
Slap
A resonance from flat surfaces, such as safety belt webbing or door trim panels.
Slip Yoke/Slip Spline
The driveshaft coupling that allows length changes to occur while the suspension articulates and while
the driveshaft rotates.
Squeak
A high- pitched transient sound, similar to rubbing fingers against a clean window.
Squeal
A long- duration, high- pitched noise.
Static Balance
The equal distribution of weight around the wheel. Statically unbalanced wheel and tire assemblies can
cause a bouncing action called wheel tramp. This condition will eventually cause uneven tire wear.
Tap
A light, rhythmic, or intermittent hammering sound, similar to tapping a pencil on a table edge.
Thump
A dull beat caused by two items striking together. Tick Klj . 9 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

WOT
The acronym for wide open throttle is WOT.
Tools and Techniques
Electronic Vibration Analyzer (EVA)
The EVA is a hand-
held electronic diagnostic tool which will assist in locating the source of
unacceptable vibrations. The vibration sensor can be remotely mounted anywhere in the vehicle for
testing purposes. The unit displays the three most common vibration frequencies and their
corresponding amplitudes simultaneously. A bar graph provides a visual reference of the relative
signal strength (amplitude) of each vibration being displayed and its relative G force. The keypad is
arranged to make the EVA simple to program and use. Some of the functions include the ability to
average readings as well as record, play back and freeze readings. The EVA has a strobe balancing
function that can be used to detect imbalance on rotating components such as a driveshaft or engine
accessories.
The EVA allows for a systematic collection of information that is necessary to accurately diagnose and
repair NVH problems. For the best results, carry out the test as follows:
a. Test drive the vehicle with the vibration sensor inside the vehicle.
b. Place the sensor in the vehicle according to feel. „If the condition is felt through the steering wheel, the source is most likely in the front of
the vehicle.
„ A vibration that is felt in the seat or floor only will most likely be found in the driveline,
drive axle or rear wheels and tires.
c. Record the readings. Also note when the condition begins, when it reaches maximum intensity, and if it tends to diminish above/below a certain speed.
„Frequencies should be read in the "average" mode. Item Description
1 EVA screen
2 Frequency mode displayed in rpm or Hz
3 Active sensor input (A or B)
4 Current active mode
5 G force indicators or the strongest frequencies in descending strength of each vibration
6 Strength of each vibration
7 Frequency in rpm/Hz of each vibration Klj . 11 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

„
Frequencies have a range of plus or minus 2. A reading of 10 Hz can be displayed as an
8 Hz through 12 Hz.
d. Place the vibration sensor on or near the suspect area outside the vehicle.
e. Continue the road test, driving the vehicle at the speed the symptom occurs, and take another reading.
f. Compare the readings.
„A match in frequency indicates the problem component or area.
„ An unmatched test could indicate the concern is caused by the engine, torque converter,
or engine accessory. Use the EVA in the rpm mode and check if concern is rpm related.
„ Example: A vibration is felt in the seat. Place the sensor on the console. Record the
readings. Place the vibration sensor on the rear axle. Compare the readings. If the
frequencies are the same, the axle is the problem component.
Vibrate Software®
Vibrate Software® ( Rotunda tool number 215- 00003) is a diagnostic aid which will assist in pinpointing
the source of unacceptable vibrations. The engine's crankshaft is the point of reference for vibration
diagnosis. Every rotating component will have an angular velocity that is faster, slower, or the same as
the engine's crankshaft. Vibrate Software® calculates the angular velocity of each component and
graphically represents these velocities on a computer screen and on a printed vibration worksheet.
The following steps outline how Vibrate Software® helps diagnose a vibration concern:
zEnter the vehicle information. Vibrate will do all the calculations and display a graph showing
tire, driveshaft and engine vibrations.
z Print a Vibration Worksheet graph. The printed graph is to be used during the road test.
z Road test the vehicle at the speed where the vibration is most noticeable. Record the vibration
frequency (rpm) and the engine rpm on the worksheet graph. The point on the graph where the
vibration frequency (rpm) reading and the engine rpm reading intersect indicates the specific
component group causing the concern.
„An EVA or equivalent tool capable of measuring vibration frequency and engine rpm will
be needed.
z Provide pictures of diagnostic procedures to aid in testing components.
Combination EngineEAR/ChassisEAR
An electronic listening device used to quickly identify noise and the location under the chassis while
the vehicle is being road tested. The ChassisEARs can identify the noise and location of
damaged/worn wheel bearings, CV joints, brakes, springs, axle bearings or driveshaft carrier bearings.
EngineEAR Basic Unit
An electronic listening device used to detect even the faintest noises. The EngineEARs can detect the
noise of damaged/worn bearings in generators, water pumps, A/C compressors and power steering
pumps. They are also used to identify noisy lifters, exhaust manifold leaks, chipped gear teeth and for
detecting wind noise. The EngineEAR has a sensing tip, amplifier, and headphones. The directional
sensing tip is used to listen to the various components. Point the sensing tip at the suspect component
and adjust the volume with the amplifier. Placing the tip in direct contact with a component will reveal
structure-borne noise and vibrations, generated by or passing through, the component. Various
volume levels can reveal different sounds.
Ultrasonic Leak Detector
The Ultrasonic Leak Detector is used to detect wind noises caused by leaks and gaps in areas where
there is weather- stripping or other sealing material. It is also used to identify A/C leaks, vacuum leaks Klj . 12 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

NOTE:
It may be necessary to have the customer ride along or drive the vehicle to point out the
concern. During the road test, take into consideration the customer's driving habits and the driving
conditions. The customer's concern just may be an acceptable operating condition for that vehicle.
The following is a brief overview of each test in the order in which it appears. A review of this
information helps to quickly identify the most appropriate process necessary to make a successful
diagnosis. After reviewing this information, select and carry out the appropriate test(s), proceeding to
the next step of this process.
zThe Slow Acceleration Test is normally the first test to carry out when identifying an NVH
concern, especially when a road test with the customer is not possible.
z The Heavy Acceleration Test helps to determine if the concern is torque- related.
z The Neutral Coast Down Speed Test helps to determine if the concern is vehicle speed- related.
z The Downshift Speed Test helps to determine if the concern is engine speed- related.
z The Steering Input Test helps to determine how the wheel bearings and other suspension
components contribute to a vehicle speed- related concern.
z The Brake Test helps to identify vibrations or noise that are brake related.
z The Road Test Over Bumps helps isolate a noise that occurs when driving over a rough or
bumpy surface.
z The Engine Run- Up Tests consist of the Neutral Run- Up Test and the Engine Load Test. These
tests help to determine if the concern is engine speed- related.
z The Neutral Run- Up Test is used as a follow- up test to the Downshift Speed Test when the
concern occurs at idle.
z The Engine Load Test helps to identify vibration/noise sensitive to engine load or torque. It also
helps to reproduce engine speed- related concerns that cannot be duplicated when carrying out
the Neutral Run- Up Test or the Neutral Coast Down Test.
z The Engine Accessory Test helps to locate faulty belts and accessories that cause engine
speed- related concerns.
z The Vehicle Cold Soak Procedure helps to identify concerns occurring during initial start- up and
when an extended time lapse occurs between vehicle usage.
Slow Acceleration Test
To carry out this test, proceed as follows:
zSlowly accelerate to the speed where the reported concern occurs. Note the vehicle speed, the
engine rpm and, if possible, determine the vibration frequency.
z Attempt to identify from what part of the vehicle the concern is coming.
z Attempt to identify the source of the concern.
z Proceed as necessary.
Heavy Acceleration Test
To carry out this test, proceed as follows:
zAccelerate hard from 0- 64 km/h (0-40 mph).
z Decelerate in a lower gear.
z The concern is torque related if duplicated while carrying out this test.
z Proceed as necessary. Klj . 6 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

Neutral Coast Down Speed Test
To carry out this test, proceed as follows:
zDrive at a higher rate of speed than where the concern occurred when carrying out the Slow
Acceleration Test.
z Place the transmission in NEUTRAL and coast down past the speed where the concern occurs.
z The concern is vehicle speed- related if duplicated while carrying out this test. This eliminates
the engine and the torque converter as sources.
z If the concern was not duplicated while carrying out this test, carry out the Downshift Speed
Test to verify if the concern is engine speed related.
z Proceed as necessary.
Downshift Speed Test
To carry out this test, proceed as follows:
zShift into a lower gear than the gear used when carrying out the Slow Acceleration Test.
z Drive at the engine rpm where the concern occurs.
z The concern is engine speed related if duplicated while carrying out this test. This eliminates the
tires, wheels, brakes and the suspension components as sources.
z If necessary, repeat this test using other gears and NEUTRAL to verify the results.
z Proceed as necessary.
Steering Input Test
To carry out this test, proceed as follows:
zDrive at the speed where the concern occurs, while making sweeping turns in both directions.
z If the concern goes away or gets worse, the wheel bearings, hubs, U- joints (contained in the
axles of 4WD applications), and tire tread wear are all possible sources.
z Proceed as necessary.
Brake Test
To carry out this test, proceed as follows:
zWarm the brakes by slowing the vehicle a few times from 80–32 km/h (50–20 mph) using light
braking applications. At highway speeds of 89–97 km/h (50– 60 mph), apply the brake using a
light pedal force.
z Accelerate to 89–97 km/h (55–60 mph).
z Lightly apply the brakes and slow the vehicle to 30 km/h (20 mph).
z A brake vibration noise can be felt in the steering wheel, seat or brake pedal. A brake noise can
be heard upon brake application and diminish when the brake is released.
Road Test Over Bumps
To carry out this test, proceed as follows: Klj . 7 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

„
Loudness proportional to vehicle speed. Low- frequency noise at high
speeds, noise and loudness increase with speed. GO to Symptom Chart —
Driveline Noise/Vibration .
„ A low- pitched noise (drumming). GO to Symptom Chart — Engine
Noise/Vibration .
„ Vibration occurs at a particular speed (mph) regardless of acceleration or
deceleration. GO to Symptom Chart — Tire Noise/Vibration .
„ Noise varies with wind/vehicle speed and direction. GO to Symptom Chart — Air Leak and Wind Noise .
„ Related to engine speed.
„Noise varies with engine rpm. GO to Symptom Chart — Engine
Noise/Vibration .
„ Vibration occurs at a particular speed (mph) regardless of engine speed
(rpm).
2. Acceleration
„Wide open throttle (WOT)
„Engine induced contact between components. Inspect and repair as
necessary.
„ Noise is continuous throughout WOT. Exhaust system or engine ground
out. GO to Symptom Chart — Engine Noise/Vibration .
„ Light/moderate acceleration
„Tip- in moan. Engine/exhaust noise. GO to Symptom Chart — Engine
Noise/Vibration .
„ Knock-type noise. GO to Symptom Chart — Engine Noise/Vibration .
„ Driveline shudder. GO to Symptom Chart — Driveline Noise/Vibration .
„ Engine vibration. GO to Symptom Chart — Engine Noise/Vibration .
3. Turning noise. GO to Symptom Chart — Steering Noise/Vibration .
4. Braking
„Clicking sound is signaling ABS is active. Acceptable ABS sound.
„ A continuous grinding/squeal. GO to Symptom Chart — Brake Noise/Vibration .
„ Brake vibration/shudder. GO to Symptom Chart — Brake Noise/Vibration .
5. Clutching
„A noise occurring during clutch operation. GO to Symptom Chart — Transmission
(Manual) and Transfer Case Noise/Vibration .
„ Vibration. GO to Symptom Chart — Transmission (Manual) and Transfer Case
Noise/Vibration .
6. Shifting
„Noise or vibration condition related to the transmission (automatic). GO to
Symptom Chart — Transmission (Automatic) Noise/Vibration .
„ Noise or vibration related to the transmission (manual). GO to Symptom Chart —
Transmission (Manual) and Transfer Case Noise/Vibration .
7. Engaged in four- wheel drive. GO to Symptom Chart — Transmission (Manual) and
Transfer Case Noise/Vibration .
8. Cruising speeds
„Accelerator pedal vibration. GO to Symptom Chart — Engine Noise/Vibration .
„ Driveline vibration. GO to Symptom Chart — Driveline Noise/Vibration .
„ A shimmy or shake. GO to Symptom Chart — Tire Noise/Vibration .
9. Driving at low/medium speeds Klj . 11 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

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
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

z
Loose rear
spring U- bolts. z
INSPECT the U- bolts.
TIGHTEN the U- bolt nuts to
specification. REFER to
Section 204 - 02 .
z Incorrect or high
CV joint
operating angle. z
CHECK vehicle ride height
is within limits. REPAIR as
necessary. REFER to
Section 206 - 00 .
z Damaged or
worn front
suspension
components. z
CHECK for a loose stabilizer
bar, damaged or loose
strut/strut bushings or loose
or worn ball joints. INSPECT
the steering linkage for wear
or damage. REPAIR or
INSTALL new components
as necessary.
z Driveline angles
out of
specification. z
CHECK for correct driveline
angles. REPAIR as
necessary. REFER to
Section 205 - 00 .
z U-joints binding
or seized. z
ROTATE the driveshaft and
CHECK for rough operation
or seized U- joints. INSTALL
new U- joints as necessary.
REFER to Section 205 - 01 .
z Binding,
damaged or
galled splines
on the driveshaft
slip- yoke z
CLEAN and INSPECT the
splines of the slip- yoke,
driveshaft and coupling
shaft for a worn, damaged
or galled condition.
INSTALL a new slip- yoke or
driveshaft assembly as
necessary. REPAIR as
necessary. REFER to
Section 205 - 01 .
z Driveline vibration—
occurs at cruising
speeds z
U-joints are
worn. z
CHECK for wear or incorrect
seating. INSTALL new U-
joints as necessary. REFER
to Section 205 - 01 .
z Worn or
damaged
driveshaft center
bearing support. z
CHECK the insulator for
damage or wear. ROTATE
the driveshaft and CHECK
for rough operation.
INSTALL a new center
bearing support as
necessary. REFER to
Section 205 - 01 .
z Loose axle
pinion flange
bolts. z
INSPECT the axle pinion
flange. TIGHTEN the pinion
flange bolts to specification.
REFER to Section 205 - 01 .
z Excessive axle
pinion flange
runout. z
CARRY OUT a Runout
Check. REPAIR as
necessary. REFER to
Section 205 - 01 .
z Driveshaft is
out-of- balance. z
CHECK the driveshaft for
damage, missing balance
weights or undercoating.
CHECK driveshaft balance. Klj . 22 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

(+40°F) or colder at
first start of the day
between ball
bearings and
bearing race.
z Power steering moan
— occurs at high idle
and possibly at idle
during the first cold
start of the day in
temperatures of
approximately - 18°C
(0°F) or colder. Noise
can even be a severe
screech for less than
one minute in very
cold temperatures of
approximately - 29°C
(- 20°F) or colder z
High fluid
viscosity, or
plugged
reservoir screen
in power
steering
reservoir
starves pump
causing
cavitation. z
Go To Pinpoint Test D .
z Generator whine —
during high electrical
loads at idle or high
idle, a high pitch
whine or moan is
emitted from the
generator z
Generator
electrical field
noise. z
Using an EngineEAR,
PROBE near the generator
housing. LISTEN for
changes in the noise level
while changing electrical
loads (such as rear defrost,
headlamps, etc.). CARRY
OUT a generator load test. If
the system passes the load
test, the noise is from the
generator bearings,
INSTALL new bearings. If
the system fails the load
test, INSTALL a new
generator. REFER to
Section 414 - 02 .
z Engine- driven cooling
fan moan — occurs
during the first start of
the day. It is most
objectionable near
idle speeds up to
2000 rpm. The noise
increases with rpm z
The viscous
cooling fan
clutch engages
until the fluid in
the clutch
reaches normal
operating
temperature,
causing the fan
to fully engage. z
Go To Pinpoint Test E .
z Drumming noise —
occurs inside the
vehicle during idle or
high idle, hot or cold.
Very low- frequency
drumming is very rpm
dependent z
Exhaust system
vibration excites
the body
resonances
inducing interior
noise.
z Engine vibration
excites the
body
resonances
inducing interior
noise. z
Go To Pinpoint Test F .
z Hissing noise —
occurs during idle or
high idle that is
apparent with the
hood open z
Vacuum leak or
idle air control
(IAC) valve flow
noise. z
Use the Ultrasonic Leak
Detector/EngineEAR to
locate the source. Scan the
air intake system from the
inlet to each cylinder intake Klj . 29 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

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
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...