While driving on interstate east of louisville kentucky at 70mph on cruise control engine stopped and vehicle coasted to shoulder of road this occurred at 4:30am june 13 when engine stopped smoke and diesel smell was apparent before vehicle coasted off road after vehicle stopped i opened engine compartment and diesel was all over engine compartment as well as on ground under vehicle i had vehicle towed and repaired with diesel in area of engine and catholitic converter i was concerned if fir hazard. i attempted to discuss matter with mercedes customer service was promised a return call which had not occurred i believe this type of failure is a dangerous fire hazard