im having the same problem at the moment but in my situation, when im crusing and let off the gas the car kind of slugs or shakes once and when i hit the gas again it shakes or slugs again. but im getting codes 71 and 74 which are missfire cyl 1 and 4 i changed the cap. rotor and plugs/wires and im still getting the codes. looking into a cyl sensor or bad ignitor...