can any 1 help ive just gota another range p38 p reg.4.6ltr on the way home on motorway doing between 70-80mph the computor went mad over an over saying transfer over heating,,refer to manual.pulled into services an allowed it to cool down. i done this all the way home an got home eventually..also steering has a mind ov its own it wonders now an again an u have to fight it!!any ideas??would a diagnostic be a good idea?