I noticed the other day that when my ac is off I have little vibration but when my ac is on it gets worse...any suggestions?

 

So does mine, and I have brand new engine mounts. I mean it's not an OMG! huge difference, but you can tell when the A/C kicks in and runs (like when idling at a stoplight). I'm guessing it's normal.

 

Yes! Stoplights drive me crazy just for this reason. I was driving one night without ac, decided to turn it on at the light and felt it viberate more. Mine was in the shop for motor mounts about two weeks ago, glad to know I'm not the only one so maybe it is normal..

 

It's sorta normal. A dirty maf sensor can cause a rough idle, gummed up throttle body, coils/plugs/wires (though usually with other symptoms), bad grounding, etc.

Mine used to vibrate until I gave it a tune up and remedied the above things. It still does in hot weather, ever so slightly.