2007 Ford F250 5.4L V8 P0505 Fault: Rough Idle and Won't Stay Running After Throttle Release
I own a 2007 Ford F250 with the 5.4L V8 engine. The vehicle is experiencing a rough idle and fails to maintain running after releasing the throttle. A diagnostic check has revealed fault code P0505, indicating an idle air control system malfunction. I have already cleaned the throttle body and replaced the throttle position sensor (TPS), but the issue persists. Notably, my truck's throttle body does not appear to have a dedicated idle air control valve. Given this, what should be my next troubleshooting step? Has anyone else encountered this specific problem with the 5.4L V8 in a 2007 F250?
If the throttle body plate and associated motor contacts have been thoroughly cleaned, the next logical step is to verify the signals being sent from the throttle body motor to the Powertrain Control Module (PCM). While I can't provide exact procedures here, there are known cases where reprogramming the PCM has helped resolve persistent low idle issues. This may be worth exploring as a potential solution.