Mechanics

T-BIRD OTHER THAN ROUGH IDLE EVERYTHING SEEMS TO WORKING FINE. ENGINE WARNING LIGHT IS ON.

1996 Ford Thunderbird • 6 cylinder 2WD Automatic • 222,000 miles

My 1996 Thunderbird is running fine and gas mileage remains good, except for the fact that it idles rough at it's normal idle of 700 to 750 rpm than automatically increases 1000 rpm smooths than dips to 500 rpm, rough again and the cycle repeats. Engine Warning light came on when this happened. What is most likely the cause?
Avatar
Mmiller6672
August 5, 2011.



How long since a tune-up? Check applicable trouble codes. Some of the national brand autostores used to check codes for free. Maybe you have a vacuum leak?

JDL
Aug 5, 2011.