I just installed by plenum spacer, and at idle the RPM's will be at around 650 (this is normal, right)? then they will drop about 100rpm's and vibrate a little then pick back up.

Is this normal?


also, is that thing supposed to SCREAM past 5K?

 

sounds like a leak.

 

+1. Check all bolts and hoses.

 

yes its supposed to scream past 5k. my car is actually quite a bit louder because of the spacer after about 3200 rpms

 

oh and yea you have a vacume leak

 

I am 90% sure that the rubber ring that goes around your oil cap is wedged between the spacer and the plenum which is causing a vacuum leak.

 

I just went out and looked, and you are 100% right. God damnit...
I even read about being careful with that too. there is a piece that is maybe a tenth of an inch wide and an maybe an inch long wedged in there. the top is torqued down pretty good, would that little tiny piece be able to cause a leak?

If so, i'll go out and rectify it right now

 

the rubber piece around the oil cap would be my guess.

 

the rpm's have been stable at 650 all day today. Could I be safe?

 

for sure vaccuum leak. spray some watch on that area and if your rpms change then you know its there