how to fix P0420 code on Ford Explorer Fifth Generation (2011-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and securely raise it with jack stands.
• Disconnect the battery.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream and downstream oxygen sensors.
2. Remove the electrical connectors by pressing the release tab.
3. Use an oxygen sensor socket to unscrew the sensors from the exhaust system.
4. Install new oxygen sensors by screwing them in place and reconnecting the electrical connectors.
   • Tools Required: Oxygen sensor socket, ratchet, torque wrench.
   • Torque Specification: 30 lb-ft for oxygen sensors.

3. Inspect and Replace Catalytic Converter

1. Remove the exhaust system components leading to the catalytic converter, including any heat shields.
2. Unscrew the catalytic converter from the exhaust pipes.
3. Inspect the old catalytic converter for signs of damage or blockage.
4. Install the new catalytic converter by aligning it with the exhaust pipes and securing it with bolts.
5. Reattach any heat shields or exhaust components removed during the procedure.
   • Tools Required: Socket set, torque wrench.
   • Torque Specification: Follow manufacturer’s specifications for bolts.

4. Check for Exhaust Leaks

1. Inspect all connections in the exhaust system for leaks.
2. Use a smoke machine or soapy water to identify any leaks.
3. Seal any leaks found using appropriate exhaust sealant or replace damaged components.

5. Final Checks

1. Reconnect the battery.
2. Start the engine and allow it to run for a few minutes.
3. Check for any leaks and listen for unusual noises.