After months of making lots of noise, it doesn’t run at all. How invlved is it to replace the blower motor of the heater/AC? What would be the best case cost estimates?
It would be helpful if you posted the make, model, and model year of your mystery vehicle. Also–does it have automatic climate control?
Very often, the devil is in the details, as the old saying says.
I Wonder If The Noise Was Caused By Leaves, Bugs, Or Part Of The Car …
… like insulation that moved out of place, etcetera, interfering with the fan. The noise was possibly a warning that unless something was done, the fan was going to go south.
Eventually the load on the motor could have blown a fuse or damaged the resistor. How involved it is depends on the specific vehicle. Fuses are very inexpensive, resistors not too bad, blower motors / fans are expensive. I went with a new resistor and used fan on my car. Difficulty of replacement can range from fairly easy to very difficult.
As VDCdriver has stated, we need more info!