Ford 2003 Mustang Workshop Manual page 2313

10. If the vehicle stalls in (D) or manual 2 at idle with vehicle at a stop, move the transmission range
selector lever to manual 1 position. If the vehicle stalls, see torque converter operation
concerns. For additional information, refer to
vehicle does not stall in (D), refer to
11. If the vehicle exhibits a vibration during the road test, complete the Road Test Evaluation Form.
This form will aid the technician in determining the source of the vibration.
NOTE: The following is a list of common vehicle concerns that have been misdiagnosed as torque
converter clutch shudder. For diagnosis of the following items refer to the appropriate sections of the
workshop manual and the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
spark plugs - check for cracks, high resistance or broken insulators
plug wires
fuel injector - filter may be plugged
fuel contamination - poor engine performance
EGR valve - valve may let in too much exhaust gas and cause engine to run lean
vacuum leak - engine will not get correct air/fuel mixture
MAP/MAF sensor - incorrect air/fuel mixture
HO2S sensor - too rich/lean air/fuel mixture
fuel pressure - may be too low
engine mounts - loose/damaged mounts can cause vibration concerns
axle joints - check for vibration
Torque Converter Road Evaluation Form
1) Does the Torque Converter
Engage/Disengage?
2) Does vibration occur during 3-4 or 4-3 shift at:
light, medium, or heavy throttle?
3) Is the problem vehicle speed dependent
Diagnosis By Symptom
Diagnosis By Symptom
Yes · GO to Step 2.
No · REFER to
Torque Converter No Apply Routine
240/340 and Always Applied Routine
241/341 in this section for further
diagnosis information. Repair as
required, verify converter operation
and then continue.
Light · May be torque converter clutch
shudder. GO to Step 3.
Medium · May be torque converter clutch
shudder. GO to Step 3.
Heavy · Not torque converter clutch shudder
— converter does not engage due to
PCM strategy. REFER to
100-04
— Noise/Vibration Routine 254/354
in this section for further diagnosis.
Yes · Not torque converter clutch shudder
in this section. If the
in this section.
Diagnosis By Symptom
and Diagnosis By Symptom
—
Section