1989 S10 Tahoe, 4.3L V6 2x4, Regular Cab-Long bed
I started the truck with the AC on cold and blower motor off. When running I switched it to hot and the blower motor on 4. After that a loud squealing/ rattling noise now is present when the truck is running only. Unplugged blower motor and sound still occur. When only power on not running with blower motor on the sound isn’t presents.