O2 Sensor: Description

The upstream O2 sensors are in the exhaust manifolds (Fig 1 ).

Fig 1: Locating Upstream Oxygen Sensor

Courtesy of DAIMLERCHRYSLER CORP.

The downstream O2 sensor are in the exhaust system near the rear axle (Fig 2 ) or (Fig 3 ).

Fig 2: Identifying Right Rear Oxygen Sensor

Courtesy of DAIMLERCHRYSLER CORP.

Fig 3: Identifying Left Rear Oxygen Sensor

Courtesy of DAIMLERCHRYSLER CORP.