See also:

Remove attached parts following use
Remove auxiliary mirrors, roof or rear luggage racks which are no longer required following use. Attached parts on the vehicle impair the aerodynamics and increase the fuel consumption. ...

Switch off the engine during longer stops
Switch off the engine during longer stops, e.g., at traffic lights, railroad crossings or in traffic congestion. Fuel savings are achieved after the vehicle is switched off for only approx. 4 s ...

Overview, instrument cluster
1 Fuel gauge 2 Speedometer 3 Indicator/warning lamps 4 Tachometer 5 Engine oil temperature 6 Electronic displays 7 Display/reset miles ...