My daughter came home from UGA yesterday complaining that the '94 945T wasn't accelerating well and was getting worse. She also complained of it being hard to start, hot or cold.

First problem I found was a hole next to the O2 sensor. I patched it until I have time to drop the DP and weld it closed.

I drove it and noticed it only bogged when entering boost. Ah hah, I say, thinking there is a hole in an intake hose. So I follow my own advice and remove every hose between the turbo and the TB. No holes. Even check the IACV hoses. Everything is firm and unblemished, inside and out. Cr*p. So my first question is...is it likely the intercooler has developed a hole?

After buttoning everything back up, I test drive it again. It acts considerably better but still bogs. Details follow... upon entering boost, it acts alright up until about 2 psi, at this point, my A/F meter indicates a sudden drop in voltage (lean condition) and it begins to bog. It does not smooth out unless I back off the accelerator. Keeping it below 2 psi boost seems to be OK but only since I ran through the hoses. Fuel pressure issue? I register 40 psi at the rail but haven't been able to check it under load. FPR doesn't leak, could it have a stiff diaphragm? Could that produce these symptoms (don't forget the difficult starting)? Car has 225k mi. and most items/sensors are still original. Engine is stock w/a not so recent head gasket change (done about 25k mi. ago).

I poke around to see if I can find the Radio Suppression relay to reflow the connections (where is it anyway?) and find the power stage connector may not be fully seated. I remove it and reseat it (one side of the retainer spring is not locking). The screws holding it to the fenderwall are stripped and do not hold it on tight. Fatter screws are in its future.

Third test drive and everything is the same except I can now maintain 5 psi boost instead of only 2. But I still cannot floor it or go over 5 psi w/o it bogging.

O2 sensor? It is original. Could the hole next to it (crack around bung) have finally killed it? I checked the waveform with a 'scope and it looks a little funky. It is varying between about .2V & .9V but the waveform isn't smooth, it has short jagged spikes at its peaks. High & low peaks vary in amplitude but the varying is not random. Doesn't look right. Not sure what the frequency is but suspect it is slower than it should be.

I think I hear an exhaust leak around the EX manifold but cannot pinpoint it.

I'll stop now. Any ideas are appreciated.
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Bob K