V70 warning light smoke acceleration

I also have a V70, though I'm not sure about the year. Your issue sounds very familiar. I experienced almost identical symptoms a while back – warning light and excessive smoke. Did you notice any change in fuel economy or engine performance besides the smoke?

Thanks for the quick response! Yes, actually, the fuel economy seems to have taken a slight hit, and the engine feels a little sluggish sometimes. Was it definitely the back pressure sensor in your case? What did you end up doing about it?

In my situation, the symptoms you describe, combined with the diagnostic code pointing to the exhaust back pressure sensor, led directly to sensor replacement. Given your additional observation of reduced fuel economy and slightly impaired engine behavior, and with the mileage you mentioned, my suggestion would be to visit a qualified workshop. They might perform more in-depth vehicle diagnostics to eliminate potential issues with the exhaust system, but it seems probable that the pressure sensor is defective. Cautious advice would be to first confirm that the sensor itself is the issue, and that there are no exhaust leaks before replacing it.

Appreciate the detailed advice! I took it to my usual mechanic, and after a quick check, it was indeed the exhaust back pressure sensor. After replacing the sensor, the warning light disappeared, the smoke is gone, and it seems like fuel consumption is back to normal! Ended up costing me 245€, parts and labor included. Thanks again for pointing me in the right direction!