Ok it all started off when I say this black Z24 in mint shape. 1988. O man Its beautiful. Mm Mmm! It had a blown 2.8. So I got it and took my 3.1 out of my 92 and put it in. Changed the TB and the EGR so that my emissions would work rite. Ran very verry well for 2 weeks. Then all of a sudden she started to run like @!#$ on me. It misses like hell on each cylinder just when its under stress. And sometimes stalls on me, Just when pulling out of my driveway. New coil packs. Still does it. Has any one els had this problem? i need help.
Could it be my pump? or regulator? or anything els?

Is it throwing any codes?

If not, it sounds just like a misfire. Once you're loading the engine, the rush of air into the cylinders blows out the spark. First reccomendation is to change plugs and wires. If you've got new plugs, wires, and coils. then it sounds like the ICM could be bad.

First I would like to say thanks for the reply SHOoff.
I am getting a code telling me to check the Oxygen sensor circuit OR I have a rich exhaust. Circuit is fine and mechanic says sensor is fine too. I was getting a MAP error code and replaced that and thats fine now. It also has new plugs and wires and coil packs.

I have yet to check the vacuum hoses to see if they have any leaks. Does any one know how many pounds of vacuum they are supposed to hold? And how many pounds of vacuum the engine pulls at idol?
Thanks