Automatic versions of the latest economy focused Audi A3 models are the first in the premium sector to benefit from the latest engine start-stop technology, which has already helped to cut emissions in manual transmission TDI versions to a sector-leading 109g/km. The new highly efficient 1.4 TFSI petrol and 1.6 TDI versions of the A3 equipped with the acclaimed S tronic twin-clutch automatic transmission will spearhead the new technology, which also goes hand-in-hand with a recuperation system to harness braking energy.
In its newly developed form for automatic applications, the start-stop system cuts engine power when the car comes to a standstill at traffic lights or in queuing traffic – the engine then remains dormant as long as the brake pedal is depressed and then restarts in just two-tenths of a second only when it is released in readiness for take-off. With the system’s help, economy is boosted and CO2 is reduced by approximately 5g/km, but if required it can be deactivated at the touch of a button.
The start-stop system is also supplemented in these models by recuperation technology, which provides further fuel and CO2 savings by recycling a proportion of the wasted kinetic energy generated under normal braking and normally dissipated as heat, and storing this temporarily in the vehicle battery to reduce the engine load when the car subsequently accelerates again. With its help, fuel usage is reduced by as much as three per cent in the A3.
Source: European Car Web