Originally Posted by tabetha

If Iwere you just as a precaution I would disconnect the fan belts, for the alternator to make sure it is that, other wise it is most likely your TIMING BELT TENSIONER, and this is very bad news.
If it is the alternator, they are relatively cheap to do, but recon is better bet as housings can crack when extracting bearings even with heating them, if they are tight which they can often be.
tabetha