I believe on the passenger side of the engine (the "front" of the engine since it's a front wheel drive, it's turned sideways in the engine compartment). On the newer (not newest, per se) model Malibu, the engine must be supported while the engine mount is removed or unbolted to replace the belt. Of course, if you are just doing the pulley, the belt can lay there until the new pulley is installed, and supporting the engine/removing th emount will not be necessary. Find the serpentine belt and it will be in contact with the tensioner pulley. Tensioners and idler pulleys are typically fairly simple to replace, and relatively inexpensive (parts at least) from what I've seen.
How do I rethread the serpentine belt on a 2002 Malibu with a V-6?
In the drivers manual if pulley has grooves belt grooves face it if pulley is slick back of belt faces it
Buy a Chevy!!!! That was a big help. Most but not all serpentine belt systems have a spring loaded tension pulley that just holds constant tension on the belt. If there is a tension pulley, it will be the one pulley that is not attached to anything like the alternator or AC. After that, the alternator is the most likely to be the one that adjusts.
There is no way to adjust the belt tensioner, if it's not keeping enough tension on the belt the complete tensioner itself will need replaced.
The tensioner is the arm on the passenger side of the engine near the front that has a pulley on the end and controls the tension of the serpentine belt. www.trailvoy.com
If you're standing at the front of the truck and looking into the engine compartment the tension pulley is on the left side about half way down.
You can change the serpentine belt by loosening the tensioner pulley. When the tensioner pulley is loose and the serpentine belt will become loose. Put the new serpentine belt on and tighten the tensioner pulley.
stand on passenger side of car with hood open and look at the pulley of the serpentine belt that is the closest to the radiator, the pump is in back of that pulley, very easy to change.
The serpentine belt on a 92 Chevy Caprice Classic is changed by loosening the tensioner pulley and pulling the belt off. A new belt can then be put in place and the tension restored.