Quote from frokki :

Same here, the wheel is momo force and it happens with all games. Off centering happens to happen after a strong ffb effect, i.e. after a crash or really, really fast countersteer. Steering the wheel from max left to max right calibrates it again, but you may imagine that it's not always possible in the middle of a race.

I had the same problem with my new momo. But I fixed that problem. I opened the wheel and cleaned the optical sensor with alcohol. I could actually see that there was some crap on the surface. Some people told me not to clean optical sensor with alcohol but it worked for me.