Hello everyone! let me begin by telling you about my car, It's a 2000 chevy cavalier, Engine: 2.4 Tranny: Manual. I have the gm supercharger installed with the re flash with a few other mods. All work was done myself. Now to the Problem..... About a month ago when i was driving it (4th gear) it started to hesitate as in jerking and seemed like it was choking out, then shifted into 5th gear same thing i started to slow down and went into 3rd gear and stepped on the gas and it cleared its self up, did that for a while then got worse it didn't idle right and had no power and would not drive, so i hauled it to my shop. messed around with it for a while, replaced fuel filter, spark plugs, coil packs the whole idi cover, i checked all my vacum lines they all seemed fine, no major vacum leak, The TPS i changed. then i found that the ground wires both on the transmission and block were lose, the one bolt stripped so i put them all together and tightened them down on the engine block, this seemed to work i drove it up and down the drive way and it seemed fine, so i drove it home, got out of town and on the highway i opened it up and it started doing the same thing again in 5 th gear and same in 4th gear? checked the ground again and it was tight. anybody have any ideas? oh and as far as codes.... It read PO171 which if i remember right was fuel trim system lean, and i forget the other code i think it was a rapid miss fire code. (other info i put the supercharger and everything else on at 54,000 miles the car currently has 70,000 miles first time i ever had a problem with the car.) any help or ideas would be great thanks