hi does anyone know what it might be d some help please i have the above transit and while driving to work this morning it went into safe mode (the glow plug light flashing on and off ) so i stopped restarted it got to about 60 and it came back on again took it to a friends tonight who plugged it in to his snap on equipment and no codes come up, the engine does not sound right and shakes from left to right hope somebody can help thanks