OK. I got an 83 Camaro Z-28, and Im not sure what it is, but when I turn my heat on the fan makes weird noises, and I can only use the defrost part to heat the car.. Does anyone have a clue what it might be and how I might be able to fix these issues.. Thanks

 

Welcome to TGO. A search on site is always useful (there's not much that hasn't been discussed on more than one occasion). Defrost is the default if there a vac leak. The usual culprit is the switch itself. Put an ear the control head and give it a listen. The noise? Could easily be a motor going out. It is 25+ years old after all.

JamesC

 

Thanks so very much. It is an old car, but I LOVE IT....

 

Oh, boy--get ready to spend some money .

JamesC

 

Ditto the welcome.

If the fan noise is like a squeeling, than it is probably the motor.
If it's like a clattering, than it's probably dirt/trash in the blower
chamber. The fan is servicable from the engine compartment, but
I don't know how hard it is to get to, with hood/fender in place.

JamesC's advice is correct as often as Rush Limbaugh (99.+%)

If the dash controller is bad, the vacuum router (which directs cabin
air flow) is definitely the weakest link -- and it's gonna be PITA to service.

Bless you for nurturing & keeping the breed alive.

 

Theres also a flap that directs air after it passes the heater core. Its right under the passanger side dash. I would imagine the sound is coming from the blower motor itself, which is the big box right under the hood on the pass side against the firewall.