when i start my car and it idles down it sits at like 1k for 2-3 minutes, then it drops and surges violently. it will jump down so the tach shows its at like 200 rpm then back to 800 up and down. I was told that this might be my IAC, but i cleaned it out and its still doing it. Can it still be the IAC or is it maybe the TPS? How can i tell besides buying new ones? Also on some cars I know the tps can get out of adjustment and using a multimeter you can adjust the tps to read the right voltage or w/e and it will work better. Is the 5.0 tps like this? if so how do i do that? thanks for the help.

 

My buddies does that when the MAF is unhooked. he has a 1992 gt and MAF clip is broke and sometimes the connector will slide off and starts loping like that.

 

my MAF is connected, i know it works because i had the tube between it and the tb off and started the engine one day. very violent surging, once i popped the tube back on it went away. Unless its only working partly.... I hate electronic crap.

 

I sent you a PM check your inbox.

 

It could be the TPS, mine surges lightly, but I haven't cleaned anything yet.