how to fix P0420 code on my Genesis G70 IG (2017-2023)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to prevent electrical shorts during repair.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors:
   • Identify the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
2. Remove the Sensors:
   • Use an oxygen sensor socket to unscrew and remove the sensors.
3. Install New Sensors:
   • Apply anti-seize compound to the threads of the new sensors.
   • Screw in the new sensors and tighten them to the manufacturer's specifications (typically around 30 lb-ft).

3. Inspect and Replace Catalytic Converter

1. Remove Exhaust Components:
   • Use a socket set to unbolt the exhaust components connected to the catalytic converter.
   • Take care to support the exhaust system to avoid damage.
2. Remove the Catalytic Converter:
   • Unbolt the catalytic converter from the exhaust manifold and the exhaust pipe.
3. Install New Catalytic Converter:
   • Position the new catalytic converter in place.
   • Secure it with bolts to the exhaust manifold and pipe, tightening to the manufacturer's torque specifications (typically around 40 lb-ft).

4. Reconnect Battery and Clear Codes

1. Reconnect Battery:
   • Reconnect the negative terminal of the battery.
2. Clear the Error Codes:
   • Use the OBD-II scanner to clear the P0420 code from the system.

5. Test Drive

• Take the vehicle for a test drive to ensure that the check engine light does not reappear and to verify that performance has improved.