Removing the belt completely might reveal 3 other possibilities

1) One of your pulleys does not turn freely (bearings)

2) There maybe sideways play/ wobble in a pulley (worn bearings)

3) The tensioner may not be tracking true due to wear

* Other than a belt or pulley problem, watch the A/C clutch while the motor is running. Sometimes the inner most part of the pulley (clutch) might drag with the a/c off and all "defrost" modes w/ heater are off....basically what I mean is, if the compressor were completely the inner part should not drag or move at all...but they do at times...could be a bad clutch.

If the noise only occurs when the A/C is on or in a heater "defrost" mode...Investigate the A/C compressor to possibly have bad bearings or getting ready to seize up

If you are able to get in there, a 3 foot or so piece of heater are garden hose may help. Shove one end in your ear, use the other like a stethoscope to pin down the noise (I have found that an earplug in your "free" ear helps too!)

WATCH OUT FOR THOSE PESKY MOVING PARTS...THEY CAN PUT A HURTIN' ON YOU ! ! !

KEEP US INFORMED

THE MEDIC

Answered by CJ MEDEVAC (expert)
6,803 answers provided