Is 02 sensor located under the car itself and not located within engine bay on my Vauxhall Astra SE CDTi 108 60 plate.

My car is jerking after a while and goes into limp mode (no engine lights) and have reduced revs.

Its been getting worse progressively car is fine on short trips but any more than say 20 minutes it starts especially when car is going uphill and under pressure.

Code shows dpf partially blocked.

Was gonna try use some cleaner directly into the dpf via the o2 sensor.

Car ne