Pontiac Repair: a/c damper door trouble, blower motor, air damper

Question
I have a 1999 Firebird base coupe with a V6. When I turn on the fan for the a/c or any other setting I hear a low fluttering noise from inside the dash. It seems like the return air damper door isn't opening. It will do this on heat or a/c and it doesn't make a difference where you set the air to come from. If you run it long enough it seems like the coil freezes up because when you shut it off it will thaw and water will run out on the floor on the passenger side.

Answer
Hey James:

it could be the recirc door that is the issue or you coulld have something that was sucked into the fan causing the air flow issue. The recirc door is inside the car and you have to gain access to it from behind the dash. on some of the car you can see it move when you change positions of the a/c knob it should move in max a/c and defrost and no other positions. you can take out the blower motor and take a look to see is something is stuck in the box or in the fan it's self. I don't have any other idea for else this could be.