Go read the post called "Vacuum reading at idle?" Chris (PkrWud) has a reply with a wealth of info on diagnosis with vacuum guage... it might help you ?
There is a way to test for a vacuum leak with a propane torch ... I believe you just turn it on (Unlit) and go around all the intake areas where you might have a vacuum leak and if you get near a leak the idle will noticably increase?? Don't quote me on that one cause i've never done it and not sure if those instructions are right ... i'm working from memory which i don't have much of !!
One of you EFI guys or girls can jump in anytime ??? Before i lead 93GTDIN down the wrong path ??
