Chugging problem in 95 lumina

Car starts and runs fine up to about cruising speed 55-60 and when the accelerator is in position to hold it at that speed it starts chugging like its missing a cylinder. You can let off and accelerate harder it wont do it, only at one position of the accelerater. TPS has already been replaced and new spark plug and wires. PCM, ICM, camshaft sensor? This thing is screwey!:screwy: All assistance greatly appreciated!

Welcome to AF, if chugging is a shudder or misfire type symptom, many things can cause this. A full scan for misfire counts, fuel trims and trans slippage codes/errors is in order to further pinpoint the problem, multiple parts replacement will not work here.