intake mani swap problems

[tegman88]

Alright guys havent really been on here much lately havent really had time to mess with the car lately but the other week i put a 08 mani on and the cars idle just went crazy its jumping up and down 2000 rpms. i have no clue what it is ive checked for vacum leakes and cant find any im using a p2r throttle body conversion kit on a j32a2 the idle was fine till i changed the mani any help can help so just throw me some ideas there use to be a thread on this problem but i dont really have time to sit here all night looking for it thanks for the help guys

[junior78]

the last guy who had the same problem it was the intake manifold itself im in the middle of doing the same swap

[RPM SYSTEMS]

it you iacv

[Singlecam_eg]

I think on V6performance there was a guy that had this problem and it ended up being the actual manifold leaking

[civicdrivr]

I had the same issues. You guys may be thinkiing of me when you said the manifold itself was leaking, because that is what I originally thought.

It wasnt the manifold, nor was it the throttle body or IACV. As a matter of fact I still dont know what the issue is.

OP - I would suggest that you check your IACV though. Even though that didnt fix anything on my car, it may fix be the issue on yours.

My IACV is constantly cracked open somewhat, so I ended up blocking it off entirely.

To check your IACV, take the intake off, start the car, and block off the lower port with your fingers. If the idle stabilizes, then replace the IACV.

[Singlecam_eg]

No the guy actually had to echange the manifold because the casting didn't seal and it had a small but problematic airgap at the seam

[Viper]

I had the same issue with the manifold swap, its the p2r gasket! 100% sure. cut and make your own tb gasket and it will not idle irregularly any further!