On the 2004 Chevy Venture, the P0131 is a very straight forward and common code on these vehicles. It’s pointing to a fault with the Oxygen Sensor for Bank1 Sensor1. The Oxygen Sensor is mounted to the exhaust manifold on the side of the engine closest to the windshield. Carefully inspect the electrical connector and as far up the wire harness as you can, looking for any loose, broken or damaged wires. If the visual inspection checks ok, replacing the Oxygen Sensor will solve the problem. Very common wear-and-tear fail item.
Does your vehicle have a similar problem? Get connected to a Live Q&A session with a certified Auto Mechanic and get your answers on this problem now!