I have a 1998 mazda millenia S it drives well except up hills and starting from a dead stop then it feels like I am pulling a boat behind me. I replaced all the plugs, new timing belt, had the tranny rebuilt, and the check enigine light reads that I need a new knock sensor. A mechanic told me that I need the Supercharger rebuilt but I am doubting his opinion since he did not look at the supercharger and isnt a mazda specialist. Anyone else ever have this much trouble? Could it be just the knock sensor?