What Does P0430 Mean on Your 2020 Nissan Maxima?
Your 2020 Nissan Maxima has triggered a P0430 code, indicating the catalytic converter on Bank 2 is not efficiently processing exhaust gases. The Maxima is powered by a 3.5L V6 engine (VQ35DE) producing 300 horsepower, paired with a CVT transmission. Bank 2 on this transverse-mounted V6 is the rear bank closest to the firewall.
As Nissan's flagship sedan, the Maxima has a powerful V6 that generates significant heat. At 4-6 years old, let's look at what might be behind the P0430 code.
Symptoms You May Notice
- Check engine light on
- Decreased fuel economy
- Sulfur or rotten egg odor from exhaust
- Slight reduction in acceleration performance
- Emissions test failure
Common Causes of P0430 on the 2020 Maxima
- Catalytic converter degradation — The 300-HP V6 generates substantial exhaust heat, and with higher mileage, converter wear is a realistic concern.
- Failed downstream O2 sensor — The Bank 2 Sensor 2 oxygen sensor may have degraded from heat exposure.
- Exhaust leak — Corrosion or loose connections can affect O2 sensor accuracy.
- Engine misfire — If the V6 has had any cylinder misfire issues, the resulting unburned fuel can damage the converter.
How to Diagnose the Problem
- Scan for all codes including misfires and O2 sensor faults
- Monitor Bank 2 O2 sensor data with a scan tool
- Inspect exhaust system for leaks and corrosion
- Check spark plug condition — V6 engines need all six firing properly
- Look for Nissan TSBs for the 2020 Maxima
Repair Options
- Catalytic converter replacement: $900–$2,000 for the 3.5L V6 Maxima.
- O2 sensor replacement: $150–$340.
- Exhaust leak repair: $100–$350.
- Spark plug replacement: $200–$380 for all six.
Cost Breakdown
- Diagnostic fee: $100–$160
- Catalytic converter: $900–$2,000
- O2 sensor: $150–$340
- Exhaust repair: $100–$350
- Spark plugs: $200–$380
The federal emissions warranty covers converters for 8 years/80,000 miles. Your 2020 Maxima may still qualify. Check with your Nissan dealer.
Prevention Tips
- Replace spark plugs at recommended intervals
- Use premium fuel as recommended for the 3.5L V6
- Address misfire codes immediately
- Have the exhaust inspected annually for corrosion
- Keep up with CVT fluid changes