Peugeot 5008 NOx Catalyst Aging and Exhaust Leak

I had a similar problem with my 5008! Check for exhaust leaks, especially around the flex pipe and joints. A small leak can throw off the whole emissions system and cause that NOx catalyst error. Is your fuel consumption higher than usual too?

Thanks! I'll check the exhaust system more thoroughly. You mentioned the flex pipe and joints, are there any specific areas I should focus on? And yes, fuel consumption has increased a bit lately.

Yeah, the flex pipe is a common failure point. Also, check the connection between the exhaust manifold and the downpipe. Since your fuel consumption is up, it definitely points to a leak messing with the O2 sensor readings. Honestly, with those symptoms, I'd just take it to a workshop and have them do a smoke test. It will save you a lot of time.

Thanks for the advice! I took it to a local shop, and you were right – it was a small crack in the exhaust manifold. They welded it up, cleared the codes, and everything seems fine now. Cost me 265€. Appreciate the help!