Engine Performance problem
2001 Ford F150 6 cyl Two Wheel Drive Manual 164, 00 miles
6 months ago I developed an engine pinging right after having the truck repainted. Mechanic said it sounded like some paint fumes got into a sensor. It should blow through. This lasted for around 50 miles and went away for a few months. It than began to happen more regularly. This began as an intermittent problem and has developed into a constant problem. Mass Flow sensor replaced(was iffy), plugs and wires replaced, coil replaced. All other sensors test good. Mainly happens during light acceleration. Not affected by temp. Happens sometimes when engine is cold or hot. Unless truck is heavily loaded, goes away under heavy acceleration. Upped octane to 89 and to 91 with no change. More persistent during street driving than highway. All throttle and air passageway have been inspected and cleaned for carbon build up. Engine computer does not register anything for fuel/air mixture problems. Developed miss on cylinder #4 just before coil was replaced.
Friday, August 21st, 2009 AT 8:11 AM