this is my first post! I have an 89 formula 305 tpi. My car idles high way to long.I can start my car car and drive for miles and the idle wont come down. But, as soon as i come to a complete stop the idles goes to normal and will stay normal untill i shut it off. Restart the car and it goes through this cycle again. I have to pull over sit at a complete stop for a couple of seconds untill normal idle returns. no vaccum leaks. replaced iac valve, tps,ect. You name it, i have replaced it

 

Welcome aboard thirdgen.org.

I don't have personal experience with TPI, but from what I've gathered here, sounds like your idle air control (IAC) needs cleaning.