Vehicle applicability: This diagnostic supplement covers multiple Ford vehicles and engines. Follow the application named in the source below. Some references apply to vehicles other than Mustang.
HU27 PRELIMINARY DIAGNOSIS FOR IDLE AIR CONCERNS
• Ignition ON, engine OFF.
Are any DTCs present other than P0505 or P0506?
Yes | No |
|---|---|
DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to Section 4, Diagnostic Trouble Code (DTC) Charts and Descriptions. | GO to HU28 . |
HU28 MONITOR THE INTAKE AIR SYSTEM RELATED PIDS
Note: Verify the vehicle has reached the normal engine coolant operating temperature of 77°C (170°F). Allow the engine to idle an additional 5 minutes.
Note: All PIDs may not be available on all vehicles.
• Access the PCM and monitor the ECT (TEMP) and ECT1 (TEMP) PIDs.
• Access the PCM and monitor the ETC_TRIM (ANGL) PID.
• Access the PCM and monitor the IACTRIM (NUM) and IACKAM2 (NUM) PIDs.
• Mathematically add and record the value of the IACTRIM PID to the IACKAM2 PID value, for the total IAC value at idle.
Is the ETC_TRIM PID angle equal to 3.5 degrees or is the total IAC value greater than 0.5 lb/min?
Yes | No |
|---|---|
INSTALL a new throttle body assembly. REFER to the Workshop Manual Section 303- 04, Fuel Charging and Controls. Clear the PCM DTCs. REPEAT the self-test. | RETURN to Section 3 , Symptom Charts for further direction. |
HU29 CHECK FOR CORRECT PCM OPERATION
• Disconnect all the PCM connectors.
• Visually inspect for:
◾ pushed out pins ◾ corrosion
• Connect all the PCM connectors and make sure they seat correctly.
• Carry out the PCM self-test.
• Verify the concern is still present.
Is the concern still present?
Yes | No |
|---|---|
INSTALL a new PCM. REFER to Section 2, Flash Electrically Erasable Programmable | The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. |
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.