Where is the belt tensioner located on 2001 Oldsmobile aurora V6 3.5 L?

The belt tensioner on a 2001 Oldsmobile Aurora V6 3.5L is located on the front of the engine, typically towards the passenger side (right side). It's usually easily visible once you've opened the hood and looked at the serpentine belt system. It will be a pulley with a mechanism (hydraulic or spring-loaded) to adjust belt tension.

However, precise location can vary slightly depending on exact engine configuration. To be absolutely sure, I highly recommend consulting a repair manual specific to your 2001 Oldsmobile Aurora 3.5L V6. A Haynes or Chilton manual will have diagrams and detailed information. You can also often find helpful diagrams online via sites like RepairPal or by searching for "2001 Oldsmobile Aurora 3.5L serpentine belt diagram."