ok, my car was slowly making a loose noise that sounded as if it was coming from the pullies, like when i would drive from the light, and tap the gas a little more, it would give me a rattle noise of some sort, like something was loose. I took it to the shop, and he said he couldnt find anything (im wondering if he even really looked for anything, specially since he didnt charge me for it) anyways, today when i was putting the new stop light switch in, i decided to go ahead and check the noise again, and while i revved up the engine from the engine bay, i noticed the noise was coming from the idler pulley, and not only that, that it would shake a little when it made the noise...this doesnt seem to normal to me.

Have any of you guys had this expeirence before? How much ball park was the price for parts? Its kinda getting on my nerves about the sound, and i want to get it fixed ASAP.

thanks