Porsche Cayenne E3 (2018-Present) check engine light and P0420 code

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative terminal of the battery to prevent electrical shorts.
• Raise the vehicle using a jack and secure it on jack stands if necessary.

2. Oxygen Sensor Replacement (if faulty)

• Tools Required: O2 sensor socket, ratchet wrench, penetrating oil.
• Apply penetrating oil to the threads of the oxygen sensors.
• Disconnect the electrical connectors from the upstream and downstream oxygen sensors.
• Use the O2 sensor socket to remove the sensors from the exhaust system.
• Install the new oxygen sensors by threading them into place and tightening to the manufacturer's specifications (typically around 30 lb-ft).
• Reconnect the electrical connectors.

3. Catalytic Converter Inspection and Replacement (if necessary)

• Tools Required: Socket set, torque wrench, gasket scraper, new gasket (if applicable).
• Inspect the catalytic converter for any visible damage or signs of blockage.
• If replacement is needed, unbolt the catalytic converter from the exhaust pipes using a socket set.
• Remove any old gasket material from the mating surfaces with a gasket scraper.
• Install the new catalytic converter with a new gasket and tighten bolts to the manufacturer’s torque specifications (usually around 30-40 lb-ft).
• Reconnect any exhaust hangers or brackets.