I have a 97 chevy Blazer 4.3 that won't run worth crap now. I replaced the fuel pump unit, spark plugs, plug wires, cap/rotartor, and ingnition coil. The truck will start then stumble to a halt seconds later. I used starter fluid to keep it running by spraying in to the throttle bore, once I stopped the start fluid feed it stumbled to a shaking halt. I am thinking it is an injector problem or injector controller problem but don't know how to go about trouble shooting this problem. Also I tested the fuel pressure at the fuel line on the engine and it reads between the 60-66 psi like it is suppose to.
I also kept getting a P0300 code for the last couple of months but then it would go away. P0300 multiple/random misfire detection. When I pulled the plugs they were all black as coal so I am assuming it's been running really rich lately.
Any help would be appreciated.
Thanks, Mav