I was wondering that too, its not throttle dependent, or rev, more like fuel consumption? It sits at around 2.0 when idling, and builds steadily when accelerating into the teens 14.0+. If you ease of at high revs, it drops back to 0.0? I wondered what this was for. Emmisions possibly. really not sure. Its a bit disconcerting driving it whilst the dash is going mad and its making noises.
M.C.