Catalyst System Efficiency Below Threshold (Bank 2)
Emission · Catalytic Converter
Same as P0420 but affects Bank 2 (passenger side on V6/V8 engines). The downstream O2 sensor reports the catalytic converter is not reducing emissions adequately.
- Worn catalytic converter Bank 2Most common
- Faulty downstream O2 sensorCommon
- Exhaust leak Bank 2Less common
Vehicles most commonly affected by P0430
Most frequently reported on V6 and V8 vehicles with dual exhaust systems: Ford F-150 (4.6L, 5.4L), Chevrolet Silverado (5.3L), Toyota 4Runner, and Dodge Ram. Bank 2 is the passenger side on most North American vehicles — the rear converter on F-150s is a particularly common failure point.
Real-world P0430 diagnosis scenario
A 2006 Ford F-150 5.4L V8 with 140,000 miles stores P0430 alongside P0420. Both catalytic converters need replacement — a common situation on high-mileage V8 trucks where both converters degrade simultaneously. The total repair cost for both converters plus four O2 sensors on this truck typically runs $1,800–$2,800 at an independent shop versus $3,500–$5,000 at a Ford dealer.
On V6 and V8 vehicles, if both P0420 and P0430 appear simultaneously, the most cost-effective repair is usually replacing both converters at once — the labor overlap is significant. Getting both done together typically costs 30–40% less than doing them separately.
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Frequently asked questions about P0430
What does P0430 mean?
Same as P0420 but affects Bank 2 (passenger side on V6/V8 engines). The downstream O2 sensor reports the catalytic converter is not reducing emissions adequately.
Is P0430 serious?
Safe to drive short-term — fix within 2 weeks.
How much does it cost to fix P0430?
Repair costs for P0430 range from $120 – $300 depending on the root cause and your vehicle.
Can I drive with P0430?
You can drive short distances but should have it repaired within 1–2 weeks to prevent further damage.
What is Bank 2 on my vehicle?
Bank 2 is the side of the engine that does NOT contain cylinder 1. On most front-wheel-drive V6 engines, Bank 2 is the rear bank (firewall side). On rear-wheel-drive V8s, Bank 2 is typically the passenger side.
Do I need to replace both catalytic converters?
Only if both P0420 and P0430 are stored. If only P0430 is stored, only the Bank 2 converter needs attention. However, if both converters are over 120,000 miles, replacing both simultaneously saves significant labor cost.
Is P0430 the same as P0420?
The fault is identical — catalytic converter efficiency below threshold — but P0430 affects Bank 2 (passenger side) while P0420 affects Bank 1 (driver side). The diagnosis and repair process is the same.