I have a problem with my f12. When I stepped on the pedal i will have a "bump"feeling of the engine and gearbox (when the car was cold, it didn't feel this way). I'm not sure it is engine , gearbox or othe parts problem. And the moment when the key turn to off it also has same feeling . I think it is the same problem. Someone tell me maybe engine mount and transmission mount but i'm not sure....pls give me some idea.