Hey guys my car has started making a weird squealing noise while my heat is on. The noise isn't always there though. Generally after about 10 min. or so the noise will start up. Once it has started it is NOT constant and it doesn't increase or decrease in volume if I turn the fun up or down. When I turn the fan off though the noise is gone.
I could only really think of two scenarios first the fan is hitting the housing, but then the volume or frequency would change when adjusting the fan. Second there is something in my vents that is being moved around or something when air contacts it.