Description: The Mopar Oxygen Sensor, Left (part number 05149180AB), plays a crucial role in monitoring exhaust gases and helping your engine control the air-fuel mixture for maximum efficiency and reduced emissions. A worn or failing sensor can cause poor fuel economy, rough idling, or even trigger the check engine light. Genuine Mopar sensors are precision-engineered for exact fit and function, delivering better reliability and performance than many generic aftermarket options.