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i have a 92 gt 3.1 auto, and it's killin me. from cold start it runs fine. will drive for a few miles until up to running temp, then all of a sudden it feels like a cylinder shut off. thats half the time. the other half before it even gets warm (driving) it just shuts of, no chugging or spuddering, just like i turned the key off. when it does that it won't start again until it cools off.i know i've read this problem on a few posts but no one has pursueed long enough to find an answer i guess? so far i have replaced.... the o2 sensor, maf, map , crank sensor, coolant temp sender, ignition control module, all three coil packs, plugs , wires , all six fuel injectors, fuel pump relay, fuel filter, and the ecm. yes i know i should've given up a long time ago, but i'm sure you can imagine how amazing this thing runs...until it takes a dump. so i guess what i'm asking is, what next? any ideas on things i should test? btw i did test the egr and the fuel pump primes everytime. please help, i love this car but theres only so much i can afford at this point

Do you have water leaks at the firewall on the passenger side? Check the ecm connector for corrosion and clean if the pins are corroded.
Use a inductance type timing light to see if you have spark when it won't start. Or stick a philips screwdriver in a plug wire, have someone crank it,
and hold the shaft near a ground while holding the plastic handle and see if you have spark. At least that will tell you if it is an ignition problem.
Are you losing coolant? If the head gasket/s are bad, pressure builds in the system until it spews into the combustion chamber and
wets the plug causing misfire and possible re-start problems. Try loosening the cooling system cap so pressure won't build and see if that helps.
If it does, you need head gaskets.
Get some starting fluid, when it won't start, take off the intake hose and have someone spray into the throttle body some spray, if it starts,
maybe your intake gaskets loosen when warm and cause a vacuum leak. Or you still have fuel delivery problems.
That's all I can think of at the moment.

A little confused on how you replaced the MAF when that year car doesn't have one...

Time to do some datalogs to see what the ECU is reading when the engine gets to this state, you could have some wiring going bad that is producing a bad reading to the ECU causing the spark to go crazy or run too rich.

oh hey good call sorry about that i was thinking of the iac...not sure how i botched that

my alternator also emits a pretty loud buzzing when the keys turned even before i start the car, a friend suggested a possible screwed up current causing the ecu to act strangely, sound feasible?or at least worth looking into?

When you replaced the ECM, did you reuse your old EPROM (chip) from the original computer?

yes i did.