how to fix P0420 code on Tesla Outback 4th Generation (2010-2014)

Solution

1. Preparation

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

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Using a socket wrench, carefully remove the oxygen sensors.
3. Inspect the sensors for any signs of damage or excessive carbon buildup.
4. If faulty, replace with new oxygen sensors (ensure they are compatible with the 2010-2014 Subaru Outback).
5. Reinstall the sensors and reconnect the wiring harness.

3. Examine and Replace the Catalytic Converter

1. Inspect the catalytic converter for physical damage or signs of clogging.
2. If replacement is necessary, use a socket set to remove the bolts connecting the catalytic converter to the exhaust system.
3. Remove the old catalytic converter and clean the mating surfaces on the exhaust pipes.
4. Install the new catalytic converter, ensuring proper alignment with the exhaust flanges.
5. Tighten the bolts to the manufacturer's specified torque settings (usually around 25-30 ft-lbs, but refer to the service manual).

4. Reconnect Battery and Clear Codes

1. Reconnect the negative battery terminal.
2. Use an OBD-II scanner to clear the P0420 code from the system.
3. Start the engine and let it run for a few minutes to ensure everything is functioning correctly.