hey everyone. Until yesterday i just shrugged this off as usual for an old TPI car but now im not so sure. When i start the car up it start and idles at about 500rpms in park then it goes up to 1500rpms then drops down to 1000 and stays there for the most part. Isn't it supposed to just start and go to 1000? Is my IAC valve faulty? I bought it not long ago but its a NAPA unit and i used to work at napa so i know all the horror stories about electronics. Also could it be related to my 9th injector? It doesn't run too smooth when its cold. The idle likes to bounce around for awhile until it warms up.

 

bump

 

come on...no ones got an answer for this one?

 

Actually these things are supposed to go to 1500 rpms at start up then slowly nudge their way back down to the idle speed over a period of time,and even when fully warmed up it will still take at least a few minutes to get back down to the final idle speed.As for why it idles at 500 to start,mine wants to do that too but you have to give the computer time to nudge that iac upwards.

 

Oh ok thanks. I didn't know if this was the way it was supposed to act or not. Ive seen a few that just start up and idle at 1000 right off the bat. but i guess every TPI car is different.

 

Well, if u have any doubts or worries read the setting TPS and IAC article on this site.

Runs you thru it step by step and make sure u start out with a clean throttle body.

later
Jeremy