Scenic exhaust back pressure sensor fault

Sounds familiar! I've got a Scenic too. Those symptoms definitely point to the exhaust back pressure sensor. If the ECU isn't getting the correct readings, it will prevent DPF regeneration and cause over-fuelling, which leads to the smoke you're seeing. Is the car down on power at all?

Thanks for the quick response! Yes, the engine feels like it's not performing as it should, especially at lower RPMs. How did you resolve your issue? Did you replace the sensor yourself, or did you take it to a garage?

Given the symptoms and the diagnostic code, it's almost certainly the sensor. I wouldn't recommend attempting the replacement yourself unless you're confident with vehicle electrics and have the right tools to reset the ECU afterwards. I'd suggest getting it checked out by a decent workshop.

Thanks a lot for the advice. I took it to the workshop, and you were spot on – the exhaust back pressure sensor was indeed faulty. They replaced it, cleared the codes, and all seems to be running smoothly now. Cost me around 245€ all in. Appreciate the help!