Oxygen Sensor: Service and Repair

REMOVAL AND INSTALLATION
Four Heated Oxygen Sensors (HO2S) are used for the engine control system. All are located in the dual converter Y pipe: one at the inlet and outlet of each catalyst converter.
1. Disconnect battery ground cable.

NOTE: When the battery has been disconnected or reconnected, some abnormal drive symptoms may occur while the Powertrain Control Module (PCM) relearns its fuel trim. The vehicle may need to be driven 16 km (10 miles) or more to relearn the fuel trim.

2. Raise vehicle on hoist.
3. Disconnect heated oxygen sensors from engine control sensor wiring.
4. Remove heated oxygen sensors from dual converter Y pipe using Oxygen Sensor Wrench T94P-9472-A.

NOTE: If excessive force is needed to remove heated oxygen sensor, lubricate heated oxygen sensor with penetrating oil prior to removal.

5. To install, reverse Removal procedure. Tighten heated oxygen sensors to 34-46 Nm (26-34 lb ft).