Originally Posted by djfllmn
sounds like the something fell down in the fan
when you put it in max ac you are closing the out side air off and recirculating the inside air. more than likely a piece of door has broken off and gotten into the fan. if so, that dash has got to come out. unless you have a large amount of time on your hands and can remember where every little screw and bolt goes back, your gonna have to take it to the shop. it AIN'T gonna be cheap. i'd put up with the sound!
Also, if you have access to an air blower, you may try and VERY LIGHTLY blow the piece out or away from the fan. blow through the ac vents. try with the blowers on and off.
*****CAUTION******* dO this at yur own risk and judgement!!!!!! i;m not gonna cover the bill if anything tears up! hahaha.