Wierd startups

[mjtr21]

I have a 99 Grand AM GT and I am getting concerned about the way the engine starts. When I go out on a cold morning to start the car I turn it to start and when the car starts, it idles wierd. The tachometer will bounce up and down and you can hear the engine reving up and down. Its as if I was pushing the gas pedal and letting off and pushing and letting off. It does this for about a minute then the rpm's steady at around 1100 rpms. I would think that it would idle higher than that on a cold morning as my cousins grand am idles at about 1500 when it is started cold. Then if I go down the road and go to gas up I shut the car off and when I go to restart it, it will start then shut off. Sometimes I have to push the gas in the get it to start. So, I am beginning to think that the IAC valve is having issues. Yesterday I took it out and cleaned it off with carb & choke cleaner and it was kinda dirty. Then I put it back in and when I started the car today it still did it but not as bad. So would I have to clean out the little hole that the valve goes into and maybe that will fix my problem? Would I just spray the cleaner in there and use a small brush? Any other suggestions for my problem? Please and Thanks.

[xeroinfinity]

What kind of temps is it in the morning ?

You can clean the IAC port, they usualy are clogged up with carbon pretty good.

Could also be a small vacum leak...
Do you have a CAI ?
If so , you will get a little funky idle when its' below 30 deg outside. What I think happens is frost builds up in the TB at start up and causes some irratic idle.

At least my GT does this sometimes, the SE always treats me right.

Both idle around 1200-1500 rpms @ start up when it's below 30.

[mjtr21]

Lately the temp has been around 20-30 when I start it up. No I dont have a CAI just regular Ram Air. I dont believe I have any vacuum leaks because I had head gasket and LIM gaskets replaced so there shouldnt be any leaks anywhere. I cleaned the port were the IAC goes in and so far no stalls. Now I just have to see how it starts cold.

[xeroinfinity]

You could have a vacum leak even though your gaskets are fine. Any of the vacum hoses under the hood cuold be leaking though causing a little higher idle.

Wouldnt hurt to check the TB butterfly and see if that's all carboned up too.

[mjtr21]

ok i will check the hoses. what is the TB butterfly ive never heard of anything like that before.

[Gir-_-]

Originally Posted by mjtr21

ok i will check the hoses. what is the TB butterfly ive never heard of anything like that before.

that is the inside valve piece of your throttle body that allows air in... when you press the petal it opens up on a horizontal axis

when you take off your air box hose thats connected to the throttle body, you'll see it inside of there, if you have carb cleaner you can open it up from the spring on the side and spray inside and all around the rim of the valve...

be careful of fumes!