Maybe a bad bearing in fan motor
The bearings are out of it. Replace Blower motor.
its your squirl cage inside of your blower motor. guaranteed. happened to me twice
it possible is the blower motor is going bad or the blower motor squirl cage is rubbing Most likely there is debri in the blower motor cage, usually mice get in there.
it sounds like the compressor drive belt is loose under the hood.or the noise may be the blower motor{blower that pushes air into your car} rule blower motor out by using fan in heat mode. Or maybe a bearing in the clutch has gone out.
If the heater blower has humming noise when motor is running, first check its capacitor. If the capacitor is fine, then the motor is the problem and may need to be replaced.
depends what type of engine you have, on a 3.3L you have to remove the steering pump before you will be able to completely remove the blower motor; on the 3.1L you have to remove the alternator before replacing the blower motor
If the noise is a squeaking sound, it could be coming from the bearings in the blower fan. It could also be coming from a worn bushing or bearing in the blower motor.
a mouse has built a nest in the the blower cage
Answertry tining the blower motor upActually I had a similar problem a while back and a supid mouse had built a nest in the line and had acorns rattling around inside the line. Just a possibility. It happens when it starts to get cold they seek shelter anywhere.
The bushing are bad.
If it's a grinding or howling sound, the heater blower motor bearing has probably dried up and ready to fail.
Probably the heater blower motor.