Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 1500 Series

Caution: Refer to Heated Oxygen and Oxygen Sensor Caution in the Preface section.

1. Remove the right wheelhouse liner. Refer to Front Wheelhouse Liner Replacement - Right Side.
2. Remove the connector position assurance (CPA) retainer (2).
3. Disconnect the HO2S electrical connector (7) from the engine wiring harness electrical connector (1).
4. Remove the HO2S clip (8) from the engine wiring harness.

Caution: Refer to Excessive Force and Oxygen Sensor Caution in the Preface section.




5. Remove the HO2S (3).

Note: A special anti-seize compound is used on the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.

Caution: Refer to Component Fastener Tightening Caution in the Preface section.




1. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.
2. Install the HO2S (3) and tighten to 42 N·m (31 lb ft).



3. Connect the HO2S electrical connector (7) to the engine wiring harness electrical connector (1).
4. Install the CPA retainer (2).
5. Install the HO2S clip (8) to the engine wiring harness.
6. Install the right wheelhouse liner. Refer to Front Wheelhouse Liner Replacement - Right Side.

Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 2500 Series

Caution: Refer to Heated Oxygen and Oxygen Sensor Caution in the Preface section.

1. Remove the right wheelhouse liner. Refer to Front Wheelhouse Liner Replacement - Right Side.
2. Remove the connector position assurance (CPA) retainer (5).
3. Disconnect the HO2S electrical connector from the engine wiring harness electrical connector (1).

Caution: Refer to Excessive Force and Oxygen Sensor Caution in the Preface section.




4. Remove the HO2S (2).

Note: A special anti-seize compound is used on the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.

Caution: Refer to Component Fastener Tightening Caution in the Preface section.




1. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.
2. Install the HO2S (2) and tighten to 42 N·m (31 lb ft).



3. Connect the HO2S electrical connector to the engine wiring harness electrical connector (1).
4. Install the CPA retainer (5).
5. Install the right wheelhouse liner. Refer to Front Wheelhouse Liner Replacement - Right Side.