Hello! I’ve had this fit for about 10k miles, bought it from a coworker for 500 bucks, it needed coils and plugs and it has been great since. It has always whined a LITTLE but suddenly very apparent. The transmission feels smooth and doesn’t shift abnormally, and never has. i know it needs a serpentine belt and that’s in the plans for next week once i have time. Just wondering if you guys have heard this noise before. Alternator is also at 14.2v

 

Could be the idler bearing

 

I can't hear it very well in your video, but here's a YouTube video that will give you an idea of what a bad idler pulley bearing sounds like in case that's what you're hearing: