99 Taurus idles high

My 3.0L 99 Ford Taurus seems to idle too high. If I am going down the road and take the transmission out of gear, the engine revs up even higher than when it was in drive, and takes forever to slow down. Just sitting in neutral, if I rev the engine, it takes forever to slow back down to a normal idle. If I disconnect the IAC, it seems fine.

I wonder if the idle air control valve is bad? When I take the electrical connector off of the IAC, this does not happen. (although it sets an engine fault...) I check the IAC with my meter, and it reads 10.3 ohms, which is supposed to be OK. But... When I take the IAC out, it does not shut all the way closed. Is there some test I can perform on it while out of the car?

Thanks in advance for any help.

Wayne
www.flymha.com

I am having the same problem with my 1996 3.0 Taurus. I notice if I take the battery cable off for a few hours it will act normal for around a week. I'm lost with this one ?? Hope someone has some ideas.

If either of you find out what the problem/solution is, please post it. I have exactly the same problem with my 99, although I had no idea what to start unplugging or checking...
Thanks to anyone that can help!!

hello, what problem we all have it must be a taurus thing because im having that same old problem and was told that it amy be my idle control unit or something like that now whos the angle to ley us all know that solutiont to the problem

My 97 Taurus did the same thing.... Mine revs to 2000 in park, and takes off sometimes way too fast. Everything is perfect when the engine is first started when it's cool, but after it's warmed up, all hell breaks loose. Noises, brake stuttering, etc. I replaced my IAC and my taurus ran fine for about a week. Then same-ol problems. I tested the voltage when I replaced it and it is supposed to read about 10v, but mine only read about 4-5. Is it the PCM? I know PCMs aren't supposed to be the culprit, but I'm beginning to wonder.

Any help?

Thanks, Anthony

My 99 Taurus does the exact same thing as Wdhille described. It is not the Idle Air Controller as I put one on from my Escort and it didn't change a thing. :mad: