Ok i'm on a quest to get rid of my high idling problem (around 2k when cold 1.6k warm). With that in mind i've checked for vacuum leaks, cleaned the TB and even replaced the IAC. None of these things have even remotely helped, and tonight just out of curiosity i put my hand over the TB intake port and pinched off a couple of vaccuum lines on the intake plenum. My car started right up and proceeded to idle around 1500 rpms. Now shouldn't it have not even started in theory cause it shouldn't have had any air. And if this theory is correct(and not just because im a noob) that would mean i have a big leak somewhere between the intake plenum and the head???? Like a blown gasket or something..this is the only thing i can think of. Any comments/suggestions/flames welcome :-)

Have you checked the Throttle position sensor? Its the senor right above the IAC. Is the butterfly plate, in the TB, slightly open during idle?

yeah according to my voltmeter everything with the TPS seems kosher. plus that still doesn't explain why my car still started and idled high when i plugged the throttle body....

if it were me, I'd be checking for a bad gasket in the manifold, or a crack in the manifold somewhere possibly

check the egr tube. it's goes right by the exhaust manifold to the intake manifold. if theres a leak it's prolly from there.

When my car was still mostly stock, i actually had several intake manifold bolts back out, and a section of the gasket FALL OUT. Big vacuum leak. Just food for thought..

Thanks for all the help guys, I was figuring it was one of these problems, and you've confirmed my suspicions. Just something to add, I am really enjoying this site. :-)

Originally posted by mastrcobb
Just something to add, I am really enjoying this site. :-)

Glad to hear it. Stick around, it gets better ;-)

Well I had the same problem, turned out to be my intake gasket, part of mine was missing too but the bolts were all tight at least. Get you some carb/throttle body cleaner and spary around the intake where it meets the head and see if it idles up. If it does you need a gasket.

I think i'm going to do that tomorrow afternoon. I went to the tool store and picked up about 3' of 3/8" drive extensions....just incase :P