How do you replace serpentine belt on 2009 Pontiac vibe. Where is the tension release?

To replace the serpentine belt on a 2009 Pontiac Vibe, first, locate the serpentine belt routing diagram, usually found on a sticker in the engine compartment. Use a ratchet or a wrench to rotate the tensioner pulley counterclockwise to relieve tension on the belt, allowing you to slip it off. Remove the old belt and install the new one, following the routing diagram. Finally, release the tensioner to secure the new belt in place.