check engine light

I recently replaced my IAC on my 99 lumina w/ 3.8.
And now the check engine light comes on. But it only comes on when I put it into park after its been driven. When in gear it idles fine, and even when its in park it idles fine.
Any thoughts???

Thanks

Have you tried to scan it for codes? This will take you one step closer to solving the problem

not yet..
hopefully this weekend..... going to call autozone to see if they pull the codes..

autozone pulled the code. said high idle.
what would cause a IAC valve to have a high idle??

Thanks

Did you ensure the pintle wasn't more than 1 1/8th inch extended before installing? Did you do the 10second on, 10 second off initialization?

And it is possible to get a bad IAC. If its an off-brand/aftermarket you probably got one. A customer brought in their 1993 olds with a stalling problem...checked the IAC, it had literally disassembled itself inside the bore. Customer said it was only 1 week old, offbrand.

The brand is Wells.
I did measure the length of the bintle, and it was the same as the old one that came out. I will recheck to make sure that its 11/8th of an inch. If its longer or shorter, how does one change the length.
Yes I did the 10 second on, and 10 second off procedure.

Thanks again!!!

Wiggle the pintle around while pushing in with moderate pressure.

Check the wiring as well, ensure nothing's broken or bad connections anywheres.

is wells an off brand???
I will be checking the pintle in the am. and if no luck with the length, will be putting old one back in, and going to dealer to get a GM part.