Air conditioning on 2008 Chevrolet Cobalt

I just purchased a 2008 chevy cobalt and when I turn the air conditioner on it makes a loud vibrating/humming noise. It also does it sometimes when the heat is on. Any idea what this might be?

by in New Hartford, NY on April 09, 2010
1 answer
ANSWER by , April 09, 2010
Probably your fan blower motor