any ideas?... i have a 92 RS 3.1 V6....when i cold start the engine flares to around 2000 rpm (sometimes higher).
the idle speed gradually reduces, taking around 10 seconds to reach 1300 rpm.
replaced the IAC but no change.

 

Mine use to do that, until I replaced injector which was a couple days ago, Not sure if that what caused it, but I know it no longer does it

 

Mine used to do that too. Right before the fuel pump went out in it. $$$ Hope thats not your case. Anyway, a dirty fuel filter could casue that. I've heard that a dirty throttle body/ICA can cause that as well. Try checking you fuel pressure at the shrader valve on your fuel rail.


~Max

 

by flares you mean it just runs at a high rpm? It's supposed to run higher when you start it cold to warm things up a bit then it'll reduce itself... Least I'm pretty sure it's supposed to run higher.

 

I think he means it revs up without him push the gas like he will be at 1500 or whatever and it will rev up to 2000

 

Right when you start the car? Mine does that too, its perfectly natural for the engine to idle high in closed loop operation; its trying to get to operating temp quickly.

 

i think the cold start idle should be around 1300rpm. fuel filter is new, iac is new, throttle body cleaned, fuel pressure is 43psi engine off & 39 psi engine idling.... i'll check out the injectors. thanks.