Guy on a Harley pulled up when he saw me gassing up my '86 3.8 SC. Said he picked up an '86 GT from an old lady for services rendered (he's a contractor). It's been garage parked since 1996, when she (by her own admission) got too large to drive it, and has only 23k original miles. With new gas, it started right up and ran fine, but randomly quits. I suggested the fuel pump was bad from condensation and sitting so long, but he says he replaced it. I'll be bringing him an ignition module next time we meet. The car is immaculate. He owns 3 or 4 Corvettes, and doesn't know if he'll keep the Fiero or sell it. Meanwhile, he's enjoying it, and would enjoy it more if it didn't randomly quit. Garaged here in Cali, didn't see any rust.
I had an issue similar to what you describe. There were two faults.
1) A previous owner had spliced into the starter positive feed (the small wire not the big one from the battery) with a suitcase connector which came loose and would intermittently cause a stall. I replaced the connector with a solder joint and the problem went away for a while.......
2) The second issue was with the ground wire for the fuel pump inside the tank. It was also loose and as a result the pump would stop working randomly. Eventually it fell off and the engine quit. I pulled the tank, removed the pump figuring I had to replace it. Imagine my surprise to see the ground wire hanging loose! I tightened up the clamp and added a metal wire to act as a safety and it has been fine since.
