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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle's battery to prevent electrical shorts.
• Allow the engine to cool if it has been running.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench, penetrating oil.
• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Apply penetrating oil to the threads of the O2 sensors to ease removal.
  3. Using the O2 sensor socket, carefully remove the sensors.
  4. Install the new O2 sensors, tightening them to the manufacturer's specified torque (usually around 30 lb-ft).
  5. Reconnect the electrical connectors.

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

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if necessary), gasket scraper.
• Sub-steps:
  1. Disconnect the exhaust system from the catalytic converter if necessary.
  2. Remove any mounting bolts or clamps holding the catalytic converter in place.
  3. Inspect the old catalytic converter for signs of damage or clogging.
  4. Install the new catalytic converter, ensuring that it is positioned correctly.
  5. Tighten all bolts to the manufacturer's torque specifications (usually around 30-50 lb-ft).
  6. Reconnect the exhaust system and check for leaks.