1998 Ford Expedition Q&A
1998 Ford Expedition Question: idle surging
My 1998 Ford expedition has a surging idle when topped or in park. It will fluctuate between 400 - 1500 rpm. I have replaced the mass air flow sensor and the vacuum line coming from the PCV valve to the rear of the air intake manifold. There is no "check engine" light on so there is no codes to look at. Does anyone have any other ideas? - Visitor
clean throd body idle up to 800.rpm change fuel filter - delane 72 garage and body shop
I would be looking at the idle air control valve, or a vacuum leak at the intake manifold, or something similar to that. - DaveJHM
when you idle the engine at 1500 rpm the idle goes up and down. when you drive at 1500 rpm the engine stumbles and misses, with a dead spot. i have replaced the following- EGR valve,EGR pressure se...