Peugeot 106 NOx Catalyst Exhaust Leak

I had a similar issue with my 106. The catalytic converter might be the problem, especially with an exhaust leak. The leak can affect the air-fuel mixture and throw off the emissions system readings, triggering the check engine light. The NOx storage catalyst is part of the catalytic converter system and reduces nitrogen oxides.

Interesting. So the exhaust leak is probably messing with the catalytic converter's efficiency, right? How did you fix your issue?

Yes, exactly. The leak is almost certainly the root cause, leading to the NOx catalyst error. I suggest you take it to a workshop to confirm, and they'll probably suggest replacing the exhaust components. Exhaust leaks upstream of the catalytic converter cause incorrect oxygen readings.

Thanks. I did take it to a workshop, and you were spot on. The exhaust system had a leak that damaged the catalytic converter, and they recommended replacing it. The repair cost 265€, but at least the car is running smoothly again.