Contour Enthusiasts Group Archives Forums General Troubleshooting extremely rough idling

My '97 Contour Sport has been idling pretty rough. Doesn't matter what season, either. Going from 500 to 1200 basically all the time. I've brought it to (2) Ford dealers, none of the ASE guys there can solve it. Brought it to my local garage, someone who I've trusted for years. He won't even take the contour/mystique, says there's an inherent problem with the engine, and Ford won't release any data on it. I've known other people with the V6 who have had similar experiences. Can they be related. Now that Ford no longer makes the vehicle here in the U.S. I'm at a loss for a solution.

Back to the idling. It's so bad, that in more than one instance, it has stalled on me downshifting to take a turn somewhere, or even slowing down at a light. Over the last 2.5 years, the O2 sensors have been replaced. The idle air control valve has been "looked at". But to no avail.

Any suggestions would be greatly appreciated. Thanks. John

Whens the last time you changed the plugs/wires?

i had the same problem with the rough idling and i changed the fuel filter and since then i havent had a problem, ya never it could be something so simple

I need to check as to when the plugs/wires were changed. Regarding the fuel filter. That was replaced about 3K ago.

I don't think it could be something that simple. I know that the dealers "supposedly" went through everything with their equipment (diagnostics and all), and couldn't find anything.

As I was searching through the forums, I noticed that someone else mentioned disconnecting the battery, and then reconnecting it? Any truth in that matter?

Disconnecting the battery will reset your computer which wont hurt, but probably wont help you in this case. If the engine runs smooth at other RPMs it would seem to point to problems with the IAC or possibly some type of intake leak. Check all the hoses around the intake area. The spark for each cylinder can be checked by pulling 1 wire at a time and noting the effect. Each wire should have about the same effect in making the car run more rough. If you find one that doesn't make a difference, then you found the bad plug or wire (or worse). Try to confirm that the ignition checks out good and then start testing the intake/fuel system. Run a bottle of injector cleaner in your next couple of tanks of gas.

Sounds like a sticking IAC valve. IAC = intake air control, it modulates the amount of air going in at idle while the throttle plate is completely closed. It is very easy to remove and clean.

-Lance

Yep, Lance is right, it's probably the IAC. I had the same problem with mine a few months after I bought it(new). They replaced it and it was fine until last December(01). You could watch the needle on the tach fluctuate(sp?) and then it would stall. I did the TH fix(not to fix the rough idle, but to stop the moosing) last month and it went away. Strange but true. Good luck.

Everyone, thanks for your input(s)! I'm going to look into your recommendations right away. Thank goodness for this forum because I'd be at a loss otherwise.