See also:

Close the windows and glasssunroof
Driving with the glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

Dual-mass flywheel with centrifugal pendulum absorber
In all road speed ranges that are relevant in everyday driving, the engineers have achieved reductions in engine speed which have noticeable benefits for fuel consumption. For example when cruisin ...

Deactivating HDC
Press the button again and the LED goes out. HDC is automatically deactivated above approx. 37 mph/60 km/h. ...