First, I'm not the mechanic many of you are here but here is what I got. I have a '91 with 4.0. It started slow for about a week but I hoped it was just the ethanol gas Now it starts hard or not at all, then sputters, stalls if I try to drive it. First I had a new crank sensor installed at a shop (blown back means I can't do the stoop, shimmy, twist under the truck anymore).Process of elimination the cam sensor, distributor cap, rotor have all been replaced. Disconnecting the MAP sensor lets it idle but not run correctly. I had the instrument cluster out chasing a short and wonder if that could have caused the problem. What am I missing? Is my ECU likely the problem? If so, smarter to have my original rebuilt or just do the exchange and any recommendations for a quality rebuilder would be appreciated. If I need another ECU will it learn the truck or do I have to take it to a shop for programming? Lots of questions but would appreciate any advice.