hi guys.. i have a moderate vibration with the a/c turned on, while sitting at idle.. not to bad in park but you can feel it when the car is in gear... when i turn off the a/c there is no vibration, and there is no vibration while driving down the road... i also noticed the a/c cooling comes and goes sometimes.. no leaks... belt feels fine... maybe the engagement clutch is slipping causing the vibration and not cooling properly?