Peugeot 406 exhaust back pressure sensor issue

I had a similar issue with my 406 diesel a while back. Same symptoms - warning light, smoke, and DPF problems. If the diagnostic points to the exhaust sensor, it's a good place to start. Did you check the sensor wiring and connections, or just read the error code?

Thanks for the quick reply! I only read the error code, I haven't checked the wiring yet. Is the sensor easy to access? And did replacing the sensor solve all your issues?

Accessing the sensor can be a bit fiddly, depending on which engine you have, but it's doable with basic tools. In my case, replacing the sensor improved things a bit, but the light came back after a while. I'd still suggest getting it checked out by a professional, as there might be more at play than just the sensor itself.

Thanks a lot for your advice. I took it to a local workshop, and you were spot on – it was the exhaust back pressure sensor! They replaced it for 245€, and now everything seems to be running smoothly again. No more smoke, no more warning light, and the DPF regeneration finally worked. Really appreciate the help!