how to fix P0420 code on Ford Explorer Sixth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the vehicle battery to prevent any electrical issues during the repair.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench, anti-seize compound.
• Remove the upstream and downstream oxygen sensors using the O2 sensor socket.
• Inspect the sensors for damage; if they are faulty, replace them with new ones.
• Apply anti-seize compound to the threads of the new sensors before installation.
• Torque the sensors to the manufacturer-specified value (typically around 30-40 lb-ft).

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

• Tools Required: Socket set, jack and jack stands, exhaust pipe cutter, gasket scraper.
• Raise the vehicle and ensure it is securely supported on jack stands.
• Disconnect the exhaust pipe from the catalytic converter using the socket set.
• Remove any bolts securing the catalytic converter to the exhaust system.
• Inspect the old catalytic converter for damage or clogging. If it is faulty, replace it with a new one.
• Install the new catalytic converter, ensuring proper alignment and secure all bolts to the specified torque.

4. Clear Codes and Test Drive

• Reconnect the vehicle battery and use the OBD-II scanner to clear any stored codes.
• Start the engine and allow it to reach operating temperature.
• Conduct a test drive to verify that the P0420 code does not return.