You'll need to determine which engine you have. Once you know the engine size, a more precise answer can be given. However, generally:
* It's usually on the top or side of the engine block, near the camshaft. It will be a small sensor with a single wire connector. You might need to remove some components (like a cover or other parts) to see it clearly.
To find it with certainty:
1. Locate your owner's manual: It may have a diagram showing the sensor location.
2. Use a repair manual: A Haynes or Chilton repair manual for your specific year and engine will have detailed diagrams and instructions.
3. Consult an online repair database: Sites like AllDataDIY (subscription required) or others offer diagrams and information.
4. Search online: A Google image search for "[Your Engine Size] Buick LeSabre camshaft position sensor location" might yield helpful images.
Caution: Before attempting to locate or replace the sensor yourself, be sure to disconnect the negative battery terminal to prevent accidental short circuits.