The computer compares the signal of the lambda probes before and after the 2 bank catalyst. If the two show almost the same, the catalyst is not holding oxygen and is not purifying enough.
Low to medium. The car drives normally, but it won't pass the emissions test, and the cause could be another engine problem.
Gasoline V- engines and engines with two catalysts. Catalytic converter, lambda probes, exhaust.
What does P0430 mean
On the V- engines, each bank of cylinders has its own catalyst and probes. "Bank 2" is the side without cylinder 1. P0430 is the same as P0420, but for the second side. If both codes are on, look for a common cause — breaks, oil, or mixture.
Symptoms
- "Check Engine" lamp, usually no change in ride
- The smell of sulfur from the exhaust
- If the catalyst is blocked - loss of power
- Failed emissions technical review
| Can it be driven?
Yes. But do not replace the catalytic converter before the cause is clear - otherwise the new one will fail in the same way.
Common reasons
- Exhausted catalyst after a long run.
- Faulty rear lambda probe of bank 2.
- Exhaust leak around the probes.
- Misfires (P0300) of the cylinders from bank 2.
- The engine burns oil or antifreeze.
- 2 bank lean or rich mix (P0174, P0175).
How we diagnose it
- We check for other codes and eliminate them first.
- We look at the signal of the probes of bank 2 when the engine is warmed up.
- We check the exhaust for leaks and the rear probe.
- For oil consumption, we measure the compression by cylinders.