2005 2.7 adjust serpentine belt

The only possibility for an adjustable "Auto-Tensioner" would be if it is spring loaded to automatically tension the belt at installation & then tighten a nut to lock it in place afterward, but then the belt would not automatically tension itself as it ages and stretches, so I would not believe what you read there. Most tensioners are spring loaded to automatically tension the belt as it wears and stretches, so if your charging system stops working because of a loose belt, then the belt has stretched to the limits of the tensioner being able to tighten it and the belt needs to be replaced. If a belt has an adjustable tensioner, then you loosen a pivot bolt and the anchoring or locking bolt, tighten the belt and lock down both bolts or nuts. Either way, the tensioner is located under the plastic timing cover on the engine and is in 2 or 3 parts. They are not the easiest bolts to get at, but you need to remove the cover to get at the tensioner. On the 2001 model, it is spring loaded so it is not adjustable to the best of my recollection so if you change the belt and it is not tight enough you will need to change the tensioner as well. I would do that anyway (which I have) but on your year I am not sure what type it has and I also believe the manufacturer recommends replacing the tensioner with the belt as well, although I am not positive about that.