got new prom engine wont start

[malletslinger]

Did you try resetting the computer after you put in the prom and the new alternator before checking the codes?
Do your gauges read accurately when there is no prom?
Take a good look at the wiring around the HEI distributer(including wires to the disributer itself at its base), look for any loose connections or melted/grounded wires. Wire exposure of any kind requires attention. There is definitely a wireing problem somewhere between your alternator and your ECM.

When your car is cold, turn the key to ON and listen for the fuel pump to kick on and off a couple of seconds later. Then remove the key from the ignition, put the prom into the computer, and do the same thing again.
Is there a difference in the fuel pumps responce to your turning the ignition to ON? Did you hear the fuel pump respond eather time?
Try to respond tomarrow morning if possible so I can think about your responce...Ive been looking at the chasis electricle system wiring diagram for your car and your answers to these Qs can help me determine where the problem might be.

[wrightz28]

Well, this might help you. My '85 was doing a similar ordeal, it would start and run for a few seconds then stall. Everything pointed to a fuel delivery problem symptomwise, but inspection and testing revealed the fuel system to be up to snuff.

Chased problems around for months with no resolve.

Got into thinking it was spark issue perhaps. However the few times I could get it to run, noone was around to help out so I could not see what the spark looked like. On Saturday in a rage of desperation i pulled the dist. out. To no surprise, the ICM had no anti heat sink grease (die-electirc) on it, the distributors shaft bushing was shot. So I figureed that was it. Wrestled it back into the car. No change.

Sunday determined this was the weekend I would bring it back to life, before nature realizes that it s/b 15* outside, not near *50. After checking the whole car up and down, went back after the dist. again. i did pick up another MAF sensor that was part of my problem so it would run, barely with a little persuation. While at the swap meet looking for a dist. (no luck, can't believe that) picked up a spark tester. Got the car started and watched it started out faintly blue then when to glowing orange in an instant.

Result was the carbon button that links the rotor to the coil was melted beyond recognition and grounding the coil within a few seconds or operation. Check your distributer very carefuly, don't assume that just because it looks good on one side means it's fine underneath.

Have you verified that the alt. is indeed putting out the 17+V the ECM claims to see?