Where is the oil sending unit on a 2006 Chevy Monte Carlo ss?

The oil pressure sending unit on a 2006 Chevy Monte Carlo SS is located on the driver's side of the engine block, near the oil filter. It's a small, usually one-wire, sensor. You'll likely need to get under the car for a clear view. Be aware that it's usually fairly close to hot engine parts, so let the engine cool down completely before attempting any work in that area.