Engine(5.2) shutters at low RPM. Replaced the MAP/EGR( which I got codes for) replaced the TPS(no code) cap & rotor, spark plugs & wires. When I replaced the plugs I noticed that one plug was black( failed to note the cylinder) the others were a light gray. A mechanic neighbor says it might be a bad fuel injector. or a short in the wiring. What do you guys think it is or might be?

 

Could be a stuck injector...does the exhaust smell rich? Unplug one injector at a time to see if Rpms change...if you find one where it doesn't you can swap it and see if behavior moves. If it moves with injector then replace it. If it stays then wiring issue.

 

I will move this to the 1st generation Dakota sub-forum.

 

You didn't say what kind of black was coating the spark plug. Is it a light dusting or chunky or goopy. I'd check compression first. Do a dry and wet test. Start with the basics.