2003 FORD MUSTANG manual transmission

A mid-
range frequency (200- 800 Hz) noise between drumming and whine. Also described as a hum.
Hum
Mid- frequency (200- 800 Hz) steady sound, like a small fan motor. Also described as a howl.
Hz
Hertz; a frequency measured in cycles per second.
Imbalance
Out of balance; heavier on one side than the other. In a rotating component, imbalance often causes
vibration.
Inboard
Toward the centerline of the vehicle.
Intensity
The physical quality of sound that relates to the strength of the vibration (measured in decibels). The
higher the sound's amplitude, the higher the intensity and vice versa.
Isolate
To separate the influence of one component to another.
Knock
A heavy, loud, repetitious sound, like a knock on the door.
Moan
A constant, low- frequency (100-200 Hz) tone. Also described as a hum.
Neutral Engine Run- Up (NERU) Test
The operation of the engine through the normal rpm range with the vehicle standing still and the
transmission disengaged. This test is used to identify engine related vibrations.
Neutralize/Normalize
To return to an unstressed position. Used to describe mounts. Refer to Bound Up.
Outboard
Away from the centerline of the vehicle.
Ping
A short duration, high- frequency sound, which has a slight echo. Klj . 7 ba
152003 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~ ...

z
Drive the vehicle over a bump or rough surface one wheel at a time to determine if the noise is
coming from the front or the back and the left or the right side of the vehicle.
z Proceed as necessary.
Neutral Engine Run- Up (NERU) Test
To carry out this test, proceed as follows:
zInstall a tachometer.
z Increase the engine rpm up from an idle to approximately 4000 rpm while in PARK on front
wheel drive vehicles with automatic transmissions, or NEUTRAL for all other vehicles. Note the
engine rpm and, if possible, determine the vibration frequency.
z Attempt to identify what part of the vehicle the concern is coming from.
z Attempt to identify the source of the concern.
z Proceed as necessary.
Drive Engine Run- Up (DERU) Load Test
To carry out this test, proceed as follows:
z WARNING: Block the front and rear wheels, and apply the parking brake and the
service brake, or injury to personnel can result.
CAUTION: Do not carry out the Engine Load Test for more than five seconds or
damage to the transmission or transaxle can result.
Block the front and rear wheels.
z Apply the parking brake and the service brake.
z Install a tachometer.
z Shift the transmission into DRIVE, and increase and decrease the engine rpm between an idle
to approximately 2000 rpm. Note the engine rpm and, if possible, determine the vibration
frequency.
z Repeat the test in REVERSE.
z If the vibration/noise is duplicated when carrying out this test, inspect the engine and
transmission or transaxle mounts.
z If the concern is definitely engine speed- related, carry out the Engine Accessory Test to narrow
down the source.
z Proceed as necessary.
Engine Accessory Test
To carry out this test, proceed as follows:
z WARNING: Block the front and rear wheels, and apply the parking brake and the
service brake, or injury to personnel can result.
CAUTION: Limit engine running time to one minute or less with belts removed or
serious engine damage will result. Klj . 8 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

z
After determining the "system", use the diagnostic tools to identify the worn or damaged
"components".
z After identifying the "components", try to find the "cause" of the failure.
Once the concern is narrowed down to a symptom/condition, proceed to NVH Condition and Symptom
Categories.
NVH Condition and Symptom Categories
A good diagnostic process is a logical sequence of steps that lead to the identification of a causal
system. Use the condition and symptom categories as follows:
zIdentify the operating condition that the vehicle is exhibiting.
z Match the operating condition to the symptom.
z Verify the symptom.
z Identify which category or system could cause the symptom.
z Refer to the diagnostic symptom chart that is referred to.
Operating Condition— Vehicle is Not Moving
1. Static operation zNoise occurs during component/system functioning. GO to Symptom Chart — Squeak
and Rattle .
2. While cranking 1. Grinding or whine, differential ring gear or starter motor pinion noise. GO to Symptom Chart — Engine Noise/Vibration .
2. Rattle. Exhaust hanger, exhaust heat shield or A/C line noise. GO to Symptom Chart —
Squeak and Rattle .
3. Vibration. Acceptable condition.
3. At idle zIdle noise. GO to Symptom Chart — Idle Noise/Vibration .
z Idle vibration or shake. GO to Symptom Chart — Idle Noise/Vibration .
4. During Gear Selection 1. Vehicle parked on a steep incline. Acceptable noise.
2. Vehicle parked on a flat surface. GO to Symptom Chart — Driveline Noise/Vibration .
3. Vehicle with a manual transmission. GO to Symptom Chart — Transmission (Manual)
and Transfer Case Noise/Vibration .
Operating Condition— Vehicle is Moving
1. Depends more on how the vehicle is operated 1. Speed related
„Related to vehicle speed
„Pitch increases with vehicle speed. GO to Symptom Chart — Tire
Noise/Vibration .
„ Noise occurs at specific vehicle speed. A high- pitched noise (whine). GO to
Symptom Chart — Driveline Noise/Vibration . Klj . 10 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~ ...

damage.
for damage. REPAIR or
INSTALL a new axle as
necessary. REFER to
Section 205 - 02A for Ford
7.5 rear axles or Section 205 - 02B for Ford 8.8
integral axles.
z Damaged or
worn wheel
bearings or axle
bearings. z
CHECK for abnormal wheel
bearing play or roughness.
REFER to Wheel Bearing Check in this section.
ADJUST or INSTALL new
wheel bearings as
necessary.
z Damaged or
worn differential
ring and pinion. z
INSPECT the ring and
pinion ring for abnormal
wear patterns or broken
teeth. INSTALL a new ring
and pinion as necessary.
REFER to Section 205 - 02A
for Ford 7.5 rear axles or
Section 205
- 02B for Ford
8.8 integral axles.
z Damaged or
worn differential
side or pinion
bearings. z
CHECK for abnormal
bearing play or roughness.
INSTALL new bearings as
necessary.
z Damaged or
worn differential
side gears and
pinion gears. z
DISASSEMBLE the
differential carrier. INSPECT
the side and pinion gears for
abnormal wear patterns or
broken teeth. INSTALL new
gears as necessary. REFER
to Section 205 - 02A for Ford
7.5 rear axles or Section 205 - 02B for Ford 8.8
integral axles.
z Driveline clunk— loud
clunk when shifting
from reverse to drive z
Incorrect axle
lubricant level. z
CHECK the lubricant level.
FILL the axle to
specification.
z Excessive
backlash in the
axle or
transmission. z
CARRY OUT a total
backlash check. REFER to
Section 205 - 00 .
z Damaged or
worn pinion
bearings. z
CHECK for abnormal
bearing play or roughness.
INSTALL new bearings as
necessary. REFER to
Section 205 - 02A for Ford
7.5 rear axles or Section 205 - 02B for Ford 8.8
integral axles.
z Damaged or
worn universal
joints (U- joints). z
INSPECT the U- joints for
wear or damage. INSTALL
new U- joints as necessary.
REFER to Section 205 - 01 .
z Loose
suspension
components. z
INSPECT the suspension
for damage or wear.
REPAIR or INSTALL new Klj . 18 ba
702003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

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

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