Transit O2 sensor corroded plug

I had a similar issue with my Transit. Check the O2 sensor wiring carefully. Is it visibly damaged or corroded?

Yeah, the plug looks pretty corroded. Is that likely the culprit? What did you end up doing?

Corrosion on the plug is a common problem. It's probably affecting the sensor's signal. I'd suggest getting it checked out at a workshop; they can properly diagnose it and replace the sensor if needed.

Thanks for the advice! Took it to a local garage, and you were spot on. It was the O2 sensor, and the corroded plug was the cause. New sensor and plug, cost me 95€ and everything's running smoothly again!