Peugeot 2008 NOx Catalyst Aging and Exhaust Leak

Sounds familiar! My old Opel Astra had similar symptoms. NOx issues can be tricky. If your exhaust is actually leaking, that's like trying to bake a cake with a hole in the oven—the system just can't regulate properly. Have you checked for obvious leaks in the exhaust system yourself?

Thank you for your quick response. About checking for leaks, could you elaborate on what I should be specifically looking for?

Sure thing. Think of it like this: your exhaust system is like a long pipe made of several sections. Check where these sections join together - that's where you are most likely to find the leak. You can usually see some soot around a crack. However, since you have experience, I suggest taking it to a workshop. A leak there is often a sign of something else amiss, and the NOx catalyst itself could be failing. It's worth getting a professional diagnosis.

I appreciate the advice. You were spot on! After inspecting the exhaust system, the mechanic found a leak, which was the primary cause of the NOx catalyst inefficiency and the error code. After repairing the leak for 265€, the error was fixed. Thank you!