What would cause rough idling? on 2000 Ford Expedition

I've already changed mass air flow, throttle position, and idle sensor and throttle body gasket but rough idling continues.

by in Hephzibah, GA on March 22, 2013
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2 answers
ANSWER by , March 22, 2013
Vacuum leak or possible low compression on one or more cylinders, eirher will smooth out with throttle.
ANSWER by , March 22, 2013
could be moisture in fuel system. try add fuel stabilizer to next tank. also may want to treat with fuel system cleaner(ethanol treatment specific). have diagnostic run. looking for exhaust issue, cat. conv. specifically. may also want to add oil stabilizer on next oil change to recondition seals and cylinders.