if it's too tight it will also make a noise and eventually snap...so if it's making a noise it's either too tight or too lose, I beleive it's a 10mm bolt on the top of the altenator in the track, slide a long screw driver between the altenator (don't break anything) and the altenator bracket and then retighten the bolt...if it doesn't seem too lose or too tight, check for rubbing on the sides of the belt, if it looks like it's fraying then the belt will be rubbing on one of your pulleys...might be a little far advanced than you're ready for.