Hey when im at a stop light and i start to go i berely press on the gas and the rpm idle goes to like 2000 and then slumps to 2100 drops again and then starts to.. feels like it jumps to go.. also if im driving around 50mph.. and have a constant pressure on the pedal(like i wont move it) and the car slows down and goes faster... at first i thought it was an exhaust leak i had, so i got it fixed, had them put in a cat cuz i didnt pass smog and now it is still doing it.. maybe spark plugs? i checked the maf and the tps and everything looks good..