New to the site, so forgive me if this is posted in the wrong area. It seemed the most populated and I need an answer pretty quick. 2011 Scion XB, looking at the front of the engine, what is the pulley on the bottom left? Grinding, wobbling and metal flakes coming off of it. Is it a tensioner, power steering or what? Tryed searching and could not find anything, thank you for any help!