Hey everyone like to say hi and apologize for my first post being a question but I'm completely stumped.I have a 1990 K2500 5.7 4x4 tbi 150k original miles one owner.One day coming home it started at run really rough at a stop light.Made it home and started messing around trying to figure out what the problem was.When I unplug the alternator field plug the truck runs great and as soon as I plug the alternator back in the truck starts to choke and fart and dies on me.
Now I've have literally replaced every sensor under the hood new distributor new ECU new EGR valve and replaced every vacuum hose there is.No vacuum leaks from the intake and I've rebuilt the TBI and a new pressure regulator.The alternator is brand new and I exchanged that for another thinking maybe the alternator was full fielding and shorting out but no dice.
Now I'm stuck and at a complete loss.Any help anyone can give me would be greatly appreciated.