2020 Honda Pilot P0430 Code Returns at 95k Miles Issue

P0430 on a 2020 Honda Pilot at 95k miles usually points to the catalytic converter on Bank 2 not reaching expected efficiency. The most likely cause is a failing catalytic converter or a rear oxygen sensor (Bank 2 Sensor 2) that’s giving false readings. Exhaust leaks near the sensors or converter can also trigger this code but are less common.

Most likely culprits

• Catalytic Converter (Bank 2): Over time, converters degrade and fail to clean emissions properly, triggering P0430.
• Rear Oxygen Sensor (Bank 2 Sensor 2): A slow or faulty sensor can mimic converter failure by reporting incorrect oxygen levels.
• Exhaust Leak near Bank 2: Leaks can cause false sensor readings and reduce converter efficiency.

How to narrow it down

1. Check for exhaust leaks around the Bank 2 converter and sensors. Listen for hissing or use soapy water on joints with the engine running. If leaks are found, fix them and clear codes.
2. Monitor rear O2 sensor voltage with a scan tool. It should fluctuate smoothly between ~0.1V and 0.9V during normal operation. A flat or slow-changing sensor suggests replacement.
3. Compare upstream and downstream O2 sensor readings on Bank 2. If downstream sensor mimics upstream closely, converter may be bad.
4. Check freeze frame and readiness monitors for any other related codes or failed monitors.
5. If sensors check out and no leaks, the catalytic converter is likely the root cause.

Possible parts (if needed)

• Rear Oxygen Sensor (Bank 2 Sensor 2)
• Catalytic Converter (Bank 2)
• Exhaust gaskets or clamps (if leaks found)

A few questions

• Did you notice any recent changes in fuel economy, power, or unusual exhaust smell?
• Has the EVAP monitor been failing for a long time or just recently?
• Any history of previous exhaust or emissions system repairs on this vehicle?