how to fix a P0131 code on GMC Sierra T1XX (2019-Present)

Learn how to diagnose and fix P0131 oxygen sensor issues in GMC Sierra T1XX. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts.
• Ensure the vehicle is on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Remove the Oxygen Sensor

• Locate the upstream oxygen sensor (usually before the catalytic converter).
• Use a socket wrench with an oxygen sensor socket to carefully unscrew the sensor.
• If the sensor is stuck, apply penetrating oil and allow it to sit before attempting removal again.

3. Inspect and Clean

• Inspect the oxygen sensor threads and the connector for any signs of damage or contamination.
• Clean the connector with electrical contact cleaner to ensure a good connection.

4. Replace the Oxygen Sensor

• Install the new oxygen sensor by threading it into place by hand to avoid cross-threading.
• Torque the sensor to the manufacturer's specifications (typically around 30-35 ft-lbs).
• Reconnect the oxygen sensor connector ensuring it clicks into place.

5. Reconnect Battery and Test

• Reconnect the negative battery terminal.
• Start the engine and allow it to reach operating temperature.
• Monitor the sensor readings with the OBD-II scanner to ensure they fluctuate appropriately and clear the P0131 code.