C3 exhaust back pressure sensor issue

I had a similar issue with my C3. Did you check the engine performance or run any vehicle diagnostics to confirm the exhaust sensor is the problem?

I haven't done a full diagnostic yet, just noticed the symptoms. What was the eventual fix for your C3?

In my case, it was definitely the exhaust back pressure sensor. Vehicle emissions were way off. I suggest going to a workshop, they will figure it out pretty fast.

Thanks. Turns out the exhaust back pressure sensor was defective. Repair cost was 245€. Appreciate the help!