i was out for a little cruise around tonight, and when i pulled over to go up this trail, i noticed a strange sound at idle. you can slightly hear it in the beginning of the video, and much more so at the end. its not the injectors ticking, but that kind of whistling/rattling? not sure how to describe it... i was thinking like loose pulley or tensioner or something? tomorrow im going to take the belt off and spin each pulley by hand and see if i can find anything.

for now, does anyone have any ideas??? (:17 to the end its the most clear)
under hood rattling - YouTube

 

Doesn't sound like a belt issue to me.

 

bump for this... took the belt off and none of the pulleys felt loose or anything, fan was solid... still cant figure out whats making this noise. :03 to :07 and then :17 - end its most clear. that whistling/humming/rattling noise that kind of comes and goes