I need a little help guys. My 95 4x4, 4.3L Voytec with 4 doors is dead in the drive way. Driving home from work at about 60 mph on the turnpike it started surgeing, and then didn't and then surged some more. Felt like the rear end was freezing up or the lockup torque converter was going bad. Made it home. Later went out and it died. It would start then die. After a couple starts and dying I had it towed to a shop I've used for years.
The shop checked ignition, fuel pressure and the computer. (App 2yrs ago they did a new fuel injection system). They thought it was a bad pcu/ecu but weren't sure and wouldn't gurantee that there might be something else wrong. I had the truck towed home.
I checked for spark and it was firing, though a little orangish. The fuel pump starts when turnning on the key like normal. ( I've installed 2 fuel pumps in 5 years.) I also put a new battery in.
I got an ecu/pcm off ebay (had it flashed to my VIN by seller) and installed it. The truck started. It ran rough at first but after driving the pcm learned and the performance was great. It was running and driving perfect. I parked it and shut it off.
Next morning I go to start it and wouldn't start. Cranked fine. I bought another pcm/ecm and installed it. Just like before it ran rough and then "learned" and was running perfect. This morning I go out to start the truck and again it wouldn't start. Turned over fine but wouldn't start.

Sorry for such a long description.
Help! Tim