here is the prob. I had the head gaskets (evil 3.8L) replaced back in May, and replaced the O2 sensor shortly after that. We reset the computer and it didnt help matters at all. The car runs jerky like its not getting enough gas, but the injectors were all replaced when the gaskets were put in, and they ran fine before the sensor was changed. The other thought we had is there is something in the exhaust. so we took the cats off and it seemed to help a bit, but its still jerky and wont rev past 3 grand when you are driving. Is it possible that all the coolant and other junk that was in the cats couldve gotten past the cats into the resonator or even into the muffler out back? its getting old having to feather the gas so it doesnt bog down, and hitting 60 is an act of God. any ideas or suggestions?