P0430 on a Honda Accord
P0430 means catalyst System Efficiency Below Threshold (Bank 2). On the Accord, a few causes come up far more than others.
What P0430 usually means on a Accord
P0430 is the bank-2 mirror of P0420 and applies to V6 Accords, which have a catalytic converter for each cylinder bank. On the J35 it usually means the front-bank converter has aged out or its rear O2 sensor has gone lazy. VCM oil consumption can accelerate converter wear on this engine. Seeing both P0420 and P0430 together points more toward a systemic cause like oil burning than two coincidental cats.
Most common causes on the Accord
- Aged bank-2 converter
The front-bank cat on high-mileage J35 Accords loses efficiency with age and heat.
- Lazy bank-2 rear O2 sensor
A slow downstream sensor on bank 2 sets P0430 without a truly bad cat.
- VCM-related oil consumption
Oil drawn past the rings on cylinder-deactivation engines coats and degrades the converter.
- Exhaust leak on bank 2
A leak ahead of the rear sensor corrupts the efficiency calculation.
What P0430 costs to fix on a Accord
Bank-2 access on the V6 is generally friendlier than bank 1, but a quality converter is still a several-hundred-dollar part. If both banks code, investigate oil consumption before buying two converters. Rear O2 sensors are the inexpensive thing to eliminate first.
Year, engine and mileage change the answer. Start a case and Redline weighs these causes against what your car shows, then names the check that would settle it.
Other codes on the Honda Accord
Related symptoms
Honda Accord problems & recalls by year
Based on widely reported patterns for this model; individual causes vary by year, engine and history. Generic P0430 behavior is covered on the main P0430 page. Confirm with a scan tool before buying parts.
P0430 on your Accord?
Every problem becomes a Case. Tell Redline what your Accord is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.
“Inner pad ~1 mm. Outer pad 3 mm.”
Next: check the slide pins move freely before buying parts.