I'm getting a P0300, P0301, and P0304, starts w/o a problem, gets sluggish at higher rpm. I had it out last night and I got on it to the point of the CEL flashing leaving me with these 3 codes.

I did a few resistance checks on the ignition coil and it seems to be ok. I also measured the resistance on fuel injectors 1 and 4 and they seem to be normal. I would find it hard to believe its plugs or wires but I was going to at least change the plugs since their cheap.

Is there something I can check or adjust on the Crankshaft Position Sensor?

I was thinking it could also be the distributor cap and rotor.

Any advise is appreciated please.

 

Ive replaced the plugs, wires, ignition coil, distributor cap and rotor, and the crankshaft position sensor.

No change, still misfires and sets off the CEL at higher rpm. Pulled the codes twice to see if it was different cylinders, got a P0303, cleared it then got P0300, 301,304.

Any ideas what else it could be?