Auto Start Stop function.
Red lights, traffic jams, road works – in everyday driving situations there are countless instances where the engine is idling, unnecessarily burning fuel. The Auto Start Stop function in the BMW Z4 Roadster switches off the engine when the vehicle stops temporarily and thus avoids unnecessary fuel consumption.
The Auto Start Stop function in the BMW Z4 Roadster (sDrive18i, sDrive20i und sDrive28i) switches off the engine as soon as the vehicle is not moving and the driver disengages the clutch (for manual transmission) or operates the brake (for Steptronic transmissions). However, intelligent electronics only switch off the engine when no energy is needed by other loads and there is no adverse effect on your safety and travelling comfort. For example, the engine remains active until the optimum running temperature has been attained or until the interior climate has reached the desired range. Depending on the type of transmission in the vehicle, when the engine has been switched off by the Auto Start Stop function, either releasing the brake or engaging the clutch will cause it to start up again automatically in a fraction of a second. The result is less fuel consumption and fewer emissions.