 01 Expedition RPM Problem
Hello To All,
I am new here and looking for some advice. I posted this in the new members section and am posting here as well in hopes of getting a better response. I have an "01" Expedition XLT 4.6L 2WD with 83,000 miles. At the stop light while idling, after the engine is warmed up, the RPM's will drop from 600 to 500 and then back up again. This will happen 2 to 3 times before the light changes. In addition the engine almost sounds like it's panting like a dog. Heavy breathing. With the heater on RPM's are stable, however the panting sound is more prominent. I've replaced the hot and cold valve, fixed a vacuum leak, and replaced the egr valve. Problem still persists. Any advice would be greatly appreciated. Thank You. | 
