Models
FORD: 2003-2005 Thunderbird, 2005-2006 Mustang, 2006-2008 Fusion, 2004-2005 Explorer, 2005-2006 Expedition, 2005-2007 F-150
LINCOLN: 2003-2006 Lincoln LS, 2006 Zephyr, 2005-2006 Navigator
MERCURY: 2006-2008 Milan
Condition
Various vehicles may exhibit diagnostic trouble codes (DTCs) P0505, P0506 and/or engine idle RPM fluctuation and hard starts. Some vehicles may also exhibit DTCs P2111 and P2112 after a keep alive memory (KAM) clear, battery disconnect or dead battery. On vehicles with over 10,000 miles, the issue may be caused by sludge buildup in the throttle body leading to less than desired airflow.
Repair Procedure
With the vehicle in park or neutral and the A/C off, start the engine and allow it to reach normal operating temperature 77 °C (170 °F).
Using a scan tool, monitor the PID values of IACTRIM and IACKAM2 while the engine is running. The sum of IACTRIM and IACKAM2 is the total IAC. Is the total IAC greater than 0.5 lb/mm?
a. Yes – proceed to Step 4.
b. No – this article does not apply.
Remove the throttle body.
Using a linkage cleaner, spray the throttle body plate and bore. Using a small, soft, solvent-resistant brush, clean the edges of the throttle plate and the mating surface of the throttle bore to remove all engine deposits (Figures 1-2).
NOTE: Avoid spraying cleaner directly into throttle plate pivot shaft bore.
Reinstall the throttle body.
Courtesy of ALLDATA
