Catalytic converter OFF (Euro 2)
Software disabling of catalytic converter monitoring and rear O2 sensors — errors P0420, P0430 and related.
The catalytic converter reduces CO and HC emissions in the exhaust gas. It is a steel housing with a ceramic or metal honeycomb coated with platinum, palladium and rhodium. Once the converter reaches its working temperature (around 600 °C), harmful compounds are oxidised as the gas passes through it.
Why catalytic converters fail
Poor fuel quality and high mileage are the main reasons. Unburnt fuel ignites inside the converter, the honeycomb overheats and melts, the effective surface shrinks and the efficiency drops. A damaged converter can also restrict the exhaust flow and reduce power.
The ECU monitors efficiency using two oxygen sensors — before and after the converter. When the signals become too similar, the ECU stores an efficiency fault:
- P0420 / P0430 — Catalyst system efficiency below threshold (bank 1 / bank 2);
- P0421, P0422, P0431, P0432 — warm-up / main catalyst efficiency below threshold.
Software solution
We disable catalyst efficiency monitoring and the downstream (post-cat) oxygen sensors in the ECU software. The procedure is also known as a "Euro 2 file" or "decat file". It can be done before or after the physical removal of the converter. Can be ordered on its own or together with Stage 1 / Stage 2.
Upload your original file and tick the option. Available with or without tuning.
Emission-related modifications (CAT, DPF/OPF, EGR, AdBlue/SCR, SAI) are supplied for off-road, motorsport and export use only, where permitted by local law. The customer is solely responsible for compliance with the regulations of their country.