94 bonneville fauling up

I have a 1994 bonneville that is tempermental. My wife was driving the car when all the sudden it dies she trys to restart it no luck. I left work which was about and hour away, about 15 minutes into my drive to her she calls and says the car started im taking it to the dealer. The dealer tells me that it needs new coils so we replaced them, we did not even pull off the lot when it died again this time they tell us camsaft sensor and ignition module, and alternater we replace that they call us at home the next day and said the car dies after about 20 minutes and loses fuel presure. A year prior to this we had the fuel pump replaced they said it needs a new pump. They did all this work and the car still does not run. When my wife startes the car and goes to roll down the window or turn on the a/c or even the radio the car dies. I am at my end with this car and do not know what else to do. You can drive it for about 20 -30 miles and then it loses power and dies. Any help would be appreciated.

Sounds like they found the problem is fuel pressure, sounds like they didnt check this first and just threw parts at it.Did they change fuel pressure regulator.Check vacuum hose going to regulator to see if there is any fuel in it.

Yeah the checked now they say that it might be the ground connection by the drives side door i guess.

That is very possible and worth to clean that up , I heard of a problem with a ground there being connected to the fuel pump

If fuel pressure is ok, does the car have a tachometer, and if so, does the tach drop to zero just prior to it stalling? If so, it sounds like a faulty crank position sensor to me. Very common problem on 3800's. Also have them inspect the harmonic balancer to see if the rubber isolator has separated from the center ring. The reluctor that triggers the crank sensor signal is attached to the rubber ring, and if separated, will cause random dying.

Ok now the car runs fine until i turn on the A/C then it shuts off they just replace the a/c compressor. can anybody tell me what is wrong i am so fed up with this car right now. It also drops in battery and electric power from 14 volts to 6 volts