Mechanics

REAL BAD RUNNING

2002 Mazda MPV

Engine Performance problem
2002 Mazda MPV 6 cyl Front Wheel Drive Automatic 73000 miles

i have been working in my wifes car, found huge vacuum leak, fixed it ( crankcase vent hose melted ) and I have sprayed " throttle body cleaner everywhere looking for other leaks, none ! ) Also codes showed a bad MAF, IAC, cylinder 1 misfire. Under any load condition engine bogs, runs rough and backfires out both ends, also has a stumble at idle, I replaced the MAF, IAC, spark plugs, TPS and air filter, I have a rock solid 18" of vacuum at idle and there is no drop at high RPM in the vacuum. And on level ground the car will maintain a smooth 75mph, ( just backfires, kicks and sputters till it gets there ) no new codes, still runs scary bad ! I dont know where to go from here, egr. Fuel pressure, ecm?
( give up and give it to a auto mech ) ( I have 30 years heavy diesel repair experience ). Help
Avatar
Mark youngkeit
June 21, 2009.



Check out the related content below while we wait for the question to be answered by a professional mechanic.