I just got together my Edel. base, the accel runners, and the matched plenum. It starts right up, but there is a LOUD vacuum leak.

The leak is coming through the passage that is below and between the throttle blades on the throttle body (kind of looks like a triangle). The passage looks like it goes down to the IAC valve. Did I screw something up?? Is the valve the problem?? I did take it out and clean it, but I don't know if I messed it up...I can put my finger over the leak when the airfoil is on and pretty much close it up. This returns the idle to around 750 rpms compared to ~1250 rpms when the port is open. Is there something I can try to diagnose this problem? I bought an IAC valve, but haven't opened it yet since I wanted to ask here first so maybe I can get my $50 back.

Thanks alot guys.
Jonathan

 

I would reset the IAC and reset the minumum air. It sounds like a loud sucking noise right? The IAC may be stuck open, thats why it idles higher than it should. Your service manual should have procedures if not, I got 'em. Let me know.