I currently got the same exact problem with my G25.

I reinstalled lfs and my G25 after 2 years not using/playing and I can't get it to work.

I set my G25 Profiler to 900° and ingame to 900°. Nevertheless I move my wheel just a couple of inch and LFS translates this as a full turn.

It is unplayable right now and I don't know what to do, to be honest