i have a 98 cavalier z24 2.4 engine. if i give it gas it chugs but if i feather the gas its ok. i tested the coil packs and ingnition control module, thats good. i changed the plugs (acdelco platiniums), plug wires and ignition coil cover. i also did a couple test with the egr, tps, and it showed no signs of it being that. i have done everthing to eliminate a spark issue and checked for vacuum leaks. could it possibly be a feul filter or injector?

check the map sensor and the hose going to it. it is very common for the hose to deteriorate and crack which causes a vacuum leak and an incorrect reading at the pcm.