my Tesla Outback 4th Generation (2010-2014) keeps throwing P0420 code, how to fix it?

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the vehicle's battery to prevent electrical shorts.
• Ensure the engine is cool before working on the exhaust system.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream and downstream oxygen sensors on the exhaust system.
2. Disconnect the electrical connectors from both sensors.
3. Use an O2 sensor socket to remove the sensors from the exhaust.
4. Install the new oxygen sensors by threading them into place; torque to manufacturer's specifications (typically 30-40 ft-lbs).
5. Reconnect the electrical connectors.

3. Inspect and Replace the Catalytic Converter (if necessary)

1. If the oxygen sensors are functioning properly, inspect the catalytic converter for damage or clogging.
2. If replacement is needed, unbolt the catalytic converter from the exhaust system using a socket set.
3. Install the new catalytic converter, ensuring proper alignment with gaskets and exhaust pipes; torque bolts to manufacturer's specifications.
4. Reconnect any exhaust hangers or brackets.

4. Clear the Codes and Test Drive

1. Reconnect the vehicle's battery.
2. Use an OBD-II scanner to clear the P0420 code from the system.
3. Start the engine and allow it to reach operating temperature.
4. Perform a test drive to monitor for any reoccurrence of the P0420 code.