I have a '90 SW that floats on the idle once warmed up. Code indicates IAC but the module tests 9 ohms. It is, however, a two pin connector. The harness has three pins. The other two parts cars here both have a three pin module, which looks like a bi-polar, rotating valve. The faulty one appears to be more like a solenoid, plunger type.

Has someone replaced it with the wrong module, or are they interchangable?

Thanks, Jim.

Is your 90 SW an automatic or manual trans?

 

The automatics got the 3-pin rotary IAC valve. the manual trans cars got the 2-pin recipricating valve.

 

If you have the correct valve, you may want to try getting a used one from a junkyard and swapping it in.

 

Have you tried clearing the codes and seeing if the IAC code comes back?

The parts cars are autos and this car is a standard. I have the valve off. It looks as if the contacts were corroded and the valve was stuck closed.It is all cleaned up, I just wasn't going to put it back on if it wasn't the right one.

All of these cars have a lot of history before I ever see them, so in some cases there is a lot of correcting to do. Quite often the only thing wrong with a car is what other people have done to it.

Thanks for the help.

Problem solved. Thanks again Josh.

Glad you got it fixed.