Mercedes-Benz has announced that the S 350 BlueTEC will be offered from now on with a standard ECO start/stop function. As a result, average fuel economy is rated at 6.2 liters/100 km (37.93 mpg US), down 9 percent from an already impressive –for the size and type of car- 6.8 liters/100 km (34.59 mpg US). Read more »