Originally Posted by EvO6-RS2

Who installed the cams? Maybe they're not lined up properly...re-check cam install...this often affects vacuum reading, idling....giving the symptoms you describe. (that's if the cams were installed at the same time...as the turbo)

Also, makesure turbo is properly bolted to manifold & turbo manifold properly bolted to head.

My friend installed a GT35r and his car idles really low sometimes & stalls...but still boost to 18psi & makes power no problem. But we haven't figure out why it idles so low as yet.

Hope that helps.

Originally Posted by Warrtalon

Gotcha. I wouldn't recommend trying to boost then, since you won't have enough fuel supply, but that unfortunately doesn't explain your strange idle behavior. It seems like it would be something vaccuum related like a big IC leak, unplugged MAF, or some disconnected hose that was missed.