Mercury XC2Z-9F472-AA Sensor - Hego

V6 models have four heated oxygen sensors. One upstream and one downstream for each cylinder head.

A special oxygen sensor socket is used to unscrew the sensor.

On V6 models, both upstream sensors are screwed into the exhaust pipes right below the exhaust manifold flanges. On 4.6L V8 models, the left upstream sensor is screwed into the exhaust manifold above the manifold flange, and the right upstream sensor is screwed into the exhaust pipe below the manifold flange. On 5.0L V8 engines, the upstream sensors are screwed into each exhaust manifold above the manifold flanges.

Disconnect the negative battery terminal. Loosen the right front wheel lug nuts, raise the vehicle, and remove the right front wheel. Remove the right lower engine splash shield. Disconnect the downstream oxygen sensor electrical connector. Unscrew and remove the downstream oxygen sensor. Apply anti-seize compound if reinstalling the old sensor. Install the sensor and tighten it to the specified torque. Reconnect the battery and allow the PCM to relearn its idle and fuel trim strategy.

YES

PART IS UPSTREAM, DOWNSTREAM IS GU2Z9G444A