My sister drives this 91 Buick Regal 3.8 V6 POS. It has a MTX amp(4 way, about 400-600 watts) powering two polk subs. This setup has been in the car for 3.5 years. What happened is the fuse on the amp's power supply(the 60 Amp fuse near the battery) melted. It didn't blow. Our mechanic tells us this fried the PCM and caused the car to run rich and give us this starting problem(he may be BSing us) So $380 and a new PCM later, the car still has the same problem. You have to crank the car forever while stepping on the gas so it won't die when it starts. I think that something else is wrong with the car, maybe some other electronic gizmo was fried?

Now why would the fuse melt? I think the amp is what caused the problem, although oddly it still worked fine until the mechanic pointed out the melted fuse. Could the fuse being melted caused other eletronic maladies, such as a fried PCM?

 

You need to check you power wire from the battery to the amp. Something in the car might have cut the insulation around it and the power wire grounded to the body and set there for a minute. Meaning when it grounded, it could have taken out a sensor or something. You know it is not the PCM now.