I have a 1993 chevy 1500 with a 350 that has a tbi unit on it. I had a vacuum leak coming from the tbi gasket so i changed it but the leak is still there right in the front of the gasket. I changed it again still the same also tried a spacer with two gaskets still same spot. So i tried a different throttle body, with the same results i thought there could only be one thing left which is the intake but after a brand new gm performer intake i still have the same gasket leak in the same spot. The engine runs great and i can hold brake clean on the leak with no problem but when the brake clean goes away the leak comes back. Any ideas?