94 Taurus engine surging at idle

Hi folks. Taurus 3.0 L surging at idle when cold. Saw some posts about cleaning " Idle air control valve"?..found it, removed it, and sprayed some carb cleaner in there. Repeated twice. Drained it out, blew dry, and replaced. No dice. PCV valve is good, and I can't find any obvious vaccuum leaks. Any help here would be appreciated. Thanks..

Reply to
John J
Loading thread data ...

"John J" wrote: 94 Taurus 3.0 L

Surges at idle when cold. Removed IAC valve, cleaned it, sprayed in some carb cleaner, and repeated twice. Drained it out, blew dry, and replaced. No dice. PCV valve is good, and I can't find any obvious vacuum leaks. Any help? ________________________________________

My car had the same symptoms, typical of a defective IAC valve. I did all of those same cleaning steps with no success. After checking out every other sensor or gadget I could think of, I went ahead and bought a new IAC valve. That fixed it.

Good luck.

Rodan.

Reply to
Rodan

You look hard enough, you will find plenty of deteriorating vacuum hoses. If there cracked, replace them. Look around the passenger side plenum first. Then there is a vacuum hose that turns into a plastic pipe then turns back into hose for the canister purge (as i recall). this goes across the engine and goes down the drivers side front down to the lower radiator area. Some of the hose may be in split loom. Look at it carefully. Change your fuel filter. Clean your maf sensor and change your air filter if you have not done it yet.

Look at your engine running at night in the dark. If you see ANY arcing or electrical activity around the plug wires, change them too. If the wires are original, you should change them anyway.

Bob

Reply to
Bob Urz

If yours is the same as the 95 version, there's a plastic tee in the vacuum line right of the manifold port. Had a high idle, surging, found it cracked.. just moving it affected the symptom. Any brass tee.

Yep... that, too. But as others say, cleaning the IAC does not always work... especially if the problem is in the motor side.

Reply to
Backyard Mechanic

Reply to
John J

Follow up..sure enough, did find another vac hose shot..replaced it. Wires looked good, no arcing, etc. Sooo.. went ahead and tried a new IAC valve. There ya go. Idling great.. nice and smooth. Got lucky I guess, although NAPA's price was steep. Thanks again for the help everyone. JJ

Reply to
John J

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.