I have a problem when my car is idling, the motor feels like it is revving up and down by itself. It's not that intense but enough that I can feel it. Does anyone know what the problem could be and how to fix it??? Thanks!

 

is your check engine light on? if it is it could be your mass air sensor, that happened to me. And one time the car got really rough and i replaced the plugs and wires and the problem was fixed. It could be a whole bunch of other stuff though. Does it fluctuate when you are decelerating, like from 4,000rpm to idle?

 

Could be a whole mess of things....you're not giving enough info. Do you get any smoke out of the exhaust? If so, what color is it? (blue, gray, black) What is the history on the maintenance on your car? How many miles? etc........

 

Maf?