Cuz the fan bearings and/or electric motor are worn...replace em. Stealership will ask about $1K for doing this. Or buy the part and have a reliable shop install for about $500 total. Or buy the part and install yourself (if ur machanically inclined) for about $200.
its probably your radiator
Your engine might make a humming noise near the alternator after you shut it down because the fan is still running or because the fuel pump is shutting down. Another cause for the humming noise could be the AC motor turning off.
There are a couple of reasons why a 2001 Audi would make humming noises from the back while it is being driven. The first thing to check is the tires. If the tires are fine, check the wheel bearings.
Its most likely a wheel bearing, I had the same problem about a year ago.
It is possible but to correctly diagnoise a noise you have to hear it.
Noises are impossible to correctly diagnoise unless you hear them. TAke it to a good diagnoistition.
The bearings are out of it. Replace Blower motor.
2001 buick lesabr // when recirculate speed doesnt change only make humming sound rest of heater works fine
it may be a a bad front wheel hub bearing or the brake calliper piston.
I have the same problem some times. I found the air filter box vibrating, which was causing the noise. I am looking for the answer to that one.
I had a very loud humming noise coming from my 99' cougar. I talked to many mechanics and nobody knew what it was. I looked it up online and found two sources( listed at bottom) that said it was the idle air control valve. I replaced the part and my car runs great without the horrible loud noise.;
It sounds like your ignition timing timing is too far advanced. It will need resetting.