key FORD MUSTANG 2003 Workshop Manual

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
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NOTE:
A serpentine drive belt decreases the usefulness of this test. In these cases, use a
vibration analyzer, such as the VA, to pinpoint accessory vibrations. An electronic listening
device, such as an EngineEAR, will also help to identify noises from specific accessories.
Remove the accessory drive belts.
z Increase the engine rpm to where the concern occurs.
z If the vibration/noise is duplicated when carrying out this test, the belts and accessories are not
sources.
z If the vibration/noise was not duplicated when carrying out this test, install each accessory belt,
one at a time, to locate the source.
Vehicle Cold Soak Procedure
To carry out this procedure, proceed as follows:
zTest preparations include matching customer conditions (if known). If not known, document the
test conditions: gear selection and engine rpm. Monitor the vibration/noise duration with a watch
for up to three minutes.
z Park the vehicle where testing will occur. The vehicle must remain at or below the concern
temperature (if known) for 6- 8 hours.
z Before starting the engine, conduct a visual inspection under the hood.
z Turn the key on, but do not start the engine. Listen for the fuel pump, anti- lock brake system
(ABS) and air suspension system noises.
z Start the engine.
z CAUTION: Never probe moving parts.
Isolate the vibration/noise by carefully listening. Move around the vehicle while listening to find
the general location of the vibration/noise. Then, search for a more precise location by using a
stethoscope or EngineEAR.
z GO to Symptom Chart — Idle Noise/Vibration to assist with the diagnosis.
6: Check OASIS/TSBs/Repair History
After verifying the customer concern, check for OASIS reports, TSBs and the vehicle repair history for
related concerns. If information relating to a diagnosis/repair is found, carry out the procedure(s)
specified in that information.
If no information is available from these sources, carry out the vehicle preliminary inspection to
eliminate any obvious faults.
7: Diagnostic Procedure
Qualifying the concern by the particular sensation present can help narrow down the concern. Always
use the "symptom" to "system" to "component" to "cause" diagnosis technique. This diagnostic method
divides the problem into related areas to correct the customer concern.
zVerify the "symptom".
z Determine which "system(s)" can cause the "symptom".
„If a vibration concern is vehicle speed related, the tire and wheel rpm/frequency or
driveshaft frequency should be calculated.
„ If a vibration concern is engine speed related, the engine, engine accessory or engine
firing frequencies should be calculated. Klj . 9 ba
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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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Component Tests
Idle Air Control (IAC) Valve
1. Open the hood.
2. NOTE: Key symptom is elevated idle speed while noise is occurring.
NOTE: "Snapping" the throttle can induce the noise.
Verify the condition by operating the vehicle for a short time.
3. Inspect the IAC valve. If physical evidence of contamination exists, install a new IAC valve. GO to
M4 .
M4 INSPECT THE FRONT DRIVESHAFT
z
NOTE: Verify that the driveshaft and pinion flange index marks
are aligned.
z Inspect the front driveshaft for missing weights, damage or
undercoating.
z Inspect the U- joints and slip yoke for freedom of movement.
z Check driveshaft runout and, if necessary, check the pinion
flange runout.
z Is the driveshaft or U- joints worn or damaged? Yes
REPAIR or INSTALL a
new driveshaft as
necessary. TEST the
system for normal
operation.
No
GO to
M5 .
M5 ROAD TEST WITH THE FRONT DRIVESHAFT ONLY
z
NOTE: Index mark the driveshaft to the pinion flange and to the
output shaft before removal.
z Remove the rear driveshaft.
z Plug the transfer case with an output shaft seal plug.
z NOTE: Shift the transfer case into 4WD high so the vehicle is
driven by the front driveshaft only.
z Test drive the vehicle.
z Is the vibration gone? Yes
INSTALL and BALANCE
the rear driveshaft.
TEST the system for
normal operation.
No
GO to
M6 .
M6 ROAD TEST WITH THE REAR DRIVESHAFT ONLY
z
NOTE: Index mark the front driveshaft to the pinion flange.
z Remove the front driveshaft.
z Test drive the vehicle.
z Is the vibration gone? Yes
INSTALL and BALANCE
the front driveshaft.
TEST the system for
normal operation.
No
GO to
M7 .
M7 TRANSFER CASE TAIL SHAFT INSPECTION
z
Inspect the splines of the output shaft for wear or damage.
z Inspect the splines of the driveshaft slip yoke for wear or
damage.
z Are the splines worn or damaged? Yes
REPAIR or INSTALL
new components as
necessary. TEST the
system for normal
operation.
No
The transfer case is OK.
CONDUCT a diagnosis
on other suspect
systems. Klj . 63 ba
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in the brake master cylinder reservoir are also indicators of system concerns.
If a wheel is locked and the vehicle must be moved, open a bleeder screw at the locked wheel (1007)
to let out enough fluid to relieve the pressure. Close the bleeder screw. This bleeding operation may
release the brakes but will not correct the cause of trouble. If this does not relieve the locked wheel
condition, repair the locked components before proceeding.
Inspect all hoses and connections. All unused vacuum connectors should be capped. Make sure
hoses and their connections are correctly secured and in good condition with no holes, soft or
collapsed areas.
Non-
Pressure Leaks
The only part of the brake system that could have a brake fluid loss that does not appear when the
system is under pressure is the brake master cylinder reservoir area. Brake fluid loss can be caused
by a missing or poorly- fitted brake master cylinder filler cap (2162), a punctured or otherwise damaged
brake master cylinder reservoir, a missing or damaged brake master cylinder filler cap gasket, or by
missing, damaged or poorly- fitted sealing grommets between the brake master cylinder (2140) and the
brake master cylinder reservoir.
The brake master cylinder reservoir grommets are not separately serviceable and must be installed
new as part of a new brake master cylinder reservoir.
Install a new flexible brake hose if it shows signs of softening, cracking or other damage.
When installing a new brake hose, position the hose to avoid contact with other vehicle components.
Road Test
Perform a road test to compare actual vehicle braking performance with the performance standards
expected by the driver. The ability of the test driver to make valid comparisons and detect performance
deficiencies will depend on experience.
The driver should have a thorough knowledge of brake system operation and accepted general
performance guidelines in order to make good comparisons and detect performance problems.
Select a road that is reasonably smooth and level. Gravel or bumpy roads are not suitable because the
surface does not allow the tires to grip the road equally. Avoid crowned roads.
A key factor in evaluating brake concerns is the deceleration rate. This varies from vehicle to vehicle
and with changes in operating conditions. It is evident how well the brakes are working after just a few
applications.
Avoid locking the brakes. Locked brakes are not an indication of braking efficiency.
Visual Inspection Chart Mechanical Electrical
z
Brake master cylinder
z Brake caliper piston
z Brake discs
z Brake pads z
Parking brake switch
z Damaged or corroded wiring harness
z Brake master cylinder fluid level switch Klj . 2 ba
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PINPOINT TEST B: THE RED BRAKE WARNING INDICATOR IS
ALWAYS ON z
Is the alignment OK? A3 CHECK THE DISC BRAKE COMPONENTS
z
Check all disc brake calipers, anchor plate guide pins and
brake pads for binding, wear, damage, contamination and
correct installation.
z Are the disc brake calipers, anchor plate guide pins
and brake pads OK? Yes
GO to
A4 .
No
REPAIR or INSTALL new
components as necessary.
RETEST for normal
operation. A4 ROAD TEST THE VEHICLE
z
Road test the vehicle, and observe whether the drift
occurs with or without the brakes applied.
z Does the drift or pull occur with the brakes applied? Yes
REPAIR or INSTALL new
front disc brake caliper or
anchor plate guide pins on
the side opposite to the
direction of the drift or pull.
No
REPAIR or INSTALL new
front disc brake caliper or
anchor plate guide pins on
the side of the vehicle in the
direction of the drift or pull.
Test Step Result / Action to Take
B1 CHECK THE BRAKE MASTER CYLINDER FLUID
LEVEL SWITCH z
Key in OFF position.
z Disconnect: Brake Master Cylinder Fluid Level Switch
C124.
z Connect a fused jumper from C124- 2 circuit 977
(PK/WH) to C124- 3 circuit 128 (VT/YE). Yes
GO to
B2 .
No
INSTALL a new brake master Klj . 7 ba
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z
Key in ON position.
z Does the brake warning indicator stay on? cylinder reservoir. TEST the
system for normal operation.
B2 CHECK PARKING BRAKE SWITCH
z
Key in OFF position.
z Disconnect: Parking Brake Switch.
z Key in ON position.
z Does the brake warning light stay on? Yes
GO to
B3 .
No
INSTALL a new parking brake
switch. TEST the system for
normal operation. B3 CHECK THE GEM
z
Key in OFF position.
z Disconnect: GEM C201e.
z Measure resistance to ground at C201e- 13.
z Is the resistance greater than 10,000 ohms? Yes
REPAIR the GEM. TEST the
system for normal operation.
No
For vehicles without Daytime
Running Lights (DRL), GO to
B4
. For vehicles with DRL, GO
to B5 .
B4 CHECK CIRCUITS 977 (VT/WH), 22 (LB/BK) AND 128
(VT/YE) z
Remove the fused jumper from C124.
z Measure the resistance to ground at C124- 2.
z Is the resistance greater than 10,000 ohms? Yes
REPAIR the ground short in
circuit 128 (VT/YE). TEST the
system for normal operation.
No
REPAIR the ground short in
circuit 977 (VT/WH) or circuit 22
(LB/BK). TEST the system for
normal operation.
B5 CHECK CIRCUIT 128 (VT/YE)
z
Remove the fused jumper from C124.
z Measure the resistance to ground at C201e- 13. Yes
GO to
B6 . Klj . 8 ba
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PINPOINT TEST D: EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL
PINPOINT TEST E: HYDRO-
BOOST, NO POWER ASSIST 4481 kPa (510-
650 psi)? INSTALL a new proportioning valve.
RETEST for normal operation.
Test Step Result / Action to Take
D1 CHECK FOR SPONGY PEDAL
z
Key in ON position.
z Operate the brake pedal and note pedal feel.
z Does the pedal feel spongy? Yes
BLEED the brake system. REFER to
Bleeding —
System in this section.
RETEST for normal operation.
No
GO to D2 .
D2 CHECK THE BRAKE PEDAL
z
Inspect the brake pedal and bracket for
binding, obstruction or damage.
z Is the brake pedal OK? Yes
GO to
D3 .
No
REPAIR or INSTALL a new brake pedal as
necessary. RETEST for normal operation. D3 CHECK THE BRAKE COMPONENTS
z
Inspect the calipers bolts, anchor plate bolts
and anti- rattle springs for binding, damage,
contamination and correct installation.
z Are the bolts and springs OK? Yes
GO to
D4 .
No
REPAIR or INSTALL new components as
necessary. RETEST for normal operation. D4 CHECK THE BOOSTER AND MASTER
CYLINDER z
Check the power brake booster and brake
master cylinder for correct installation and
correct push rod adjustment. Refer to
Section 206 - 06 and to Section 206 - 07 .
z Are the power brake booster and the
brake master cylinder OK? Yes
INSPECT the front wheel bearings for
wear, damage and correct installation and
the rear axle end play. CORRECT as
necessary. RETEST for normal operation.
No
CORRECT as necessary. RETEST for
normal operation.
Test Step Result / Action to Take
E1 CHECK FLUID LEVEL IN POWER STEERING
PUMP z
Check fluid level in power steering pump.
z Is level within specification? Yes
GO to
E2 .
No
CHECK for leakage of power steering
fluid. ADD fluid as necessary. E2 CHECK ACCESSORY DRIVE BELT Klj . 10 ba
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