hi guys I'm new to this forum and figured I'd try it out, my b20z2 swapped eg sedan is having a problem, once you turn it on it just revs by it self to 3-4K Rmps and goes back down to idle and then back to 3-4k Rmps and doesn't stop I've tried changing the throttle body gasket but it still does it, does anybody know what it could be?

 

1. Check for any vacuum leaks
2. Unbolt and clean your IACV from back of manifold.
I would start there. Good luck. If you don't know the vacuum diagram or where the IACV is, google and youtube will help you figure it out..

 

Alright thanks I'll try that

 

Let us know if that solves your problem. Sounds like you have a "hunting Idle" . There are other reasons it could be idling bad such as an air bubble in the coolant system. We are all assuming you haven't done any kind of work on the car and these symptoms have just surfaced.

 

Sounds like a massive vacuum or intake air leak.