I just bought an 89 Trans Am with the 305 TPI. Whenever im trying to maintain a speed (just giving it a little gas) the tachometer bounces between 1000-2750 rpm and the car hesitates. I changed the plugs, wires, rotor and cap but this did absolutely nothing. Also, i started the car up after 2 weeks of the car sitting and the car was running real rough and the tach was bouncing up to 3250 and back down to idle really fast. We ran a diagnostic checker and we didnt find any error codes. Does anyone have any ideas to what the problem could be?