Question : 95 Buick Century 3100 high rev at start up

[blackrosetiger]

I have a 95 Buick Century with a 3100. When I first start it up on cold winter days it revs real high (Im guessing around 7-8k rpms) then settles back down to a normal idle. It also has a slight tick but only with a cold engine. Any ideas as to what is causing this?

[LeftVentricle]

It's unlikely it's going to seven or eight thousand, since these engines redline closer to 6000 in stock form, and the rev limiter in park/neutral is much lower than that. Your car probably doesn't have a tachometer and you're guessing since it does make an awful racket when it revs real high.

I think the idle speed control might be malfunctioning a bit.

[pocket-rocket]

I would concur. Maybe pull out the IAC and shoot it with some carb and choke cleaner. If it were a vacuum leak (a large one like a brake booster or intake manifold gaskets) it would do it all the time and not settle down (if it would even idle).

[bszopi]

Park/neutral rev limiter is around 3k, so that is probably as high as it will go. Concur with the IAC.

[blackrosetiger]

Thanks guys that at least gives me a starting point