Hodgie

I've had this car for about 4 years. I've always noticed it starts a bit rough when the engine is cold. I've heard this is typical noise from the 3.0??? When i have the heater or a/c unit set to Auto, I hear a loud noise come from the front of the engine - lasts only a couple of seconds & sounds like an old refrigerator starting up. When heater or a/c is off there is no noise. Anyone else hear these unsettling noises with the 3.0L?? I take it for regular maintenance at the dealer (yes, I know I'm paying too much) and they tell me everything is normal with the car.