[danielt]

That was one of the first things I looked for. I sprayed the intake down with carb cleaner trying to find a leak. I am using a 1989 Carrera manifold with SDSEFI system. When it went bad, it was instantaneous. I was cruising down the freeway at 75mph, and it just died...
Only way I could get it to run was to lean it way out...
A vacuum leak would lower the manifold pressure causing the EFI to increase the fuel delivery so that is a potential for making it run rich. However, that would not explain the bank-to-bank delta in compression test....
Never hurts to check it again, so I'll add that to the tests for this week.