HUGE vacuum leak Options

[match220]

This is very frustrating. The engine is Gen3 3sgte, tons of mods, aftermarket ecu, etc, etc. I finally got it running, but once it starts it jumps up to 4k rpm, which is very unsafe on a new engine, not to mention dangerously unsafe without it being tuned yet. All I have is the base fuel and ignition maps and I haven't adjusted any of the fuel or ignition values. The engine could blow revving up this high, so I only start it long enough to see what it idles at, but it immediately jumps to 4k rpm, so I shut it off immediately.

What i've checked so far... I've plugged every vacuum hose and looked for cracks (even though cracks wouldn't make it rev this high). I've plugged the IACV and shut it off in the aftermarket ecu. I checked all of the threaded holes that were used as mounts to make sure they don't go to the inside of the manifold. I even adjusted the idle screw down completely so the TB butterfly is closed completely. I pulled the hose off of the turbo by the TB. I am not letting it run longer than a couple seconds when I start it just for safety.

This leads me to a few possibilities, cracked intake manifold (even though I checked that a long time ago), something between the manifold and the head preventing the gasket from being flush. A leak in the TB butterfly spring assembly, or TPS assembly.

I'm going to borrow an air compressor from a friend and force air into it through a vacuum hose to see if I can hear where the leak is.

If any of you guys have any ideas other than what's mentioned please tell me. Thanks!

This post has been edited by match220: Mar 5, 2013 - 9:08 PM