Audi pairs start-stop with S tronic automatic on A3 diesels and petrols
Audi has introduced its start-stop system on the A3 1.6 TDI and 1.4 TFSI models with S tronic dual-clutch automatic, aiming to cut fuel use and emissions in urban driving.
Audi has made its start-stop system available with an automatic transmission for the first time, pairing the technology with its S tronic dual-clutch gearbox on selected A3 models. The move, announced for the A3 1.6 TDI and 1.4 TFSI, targets drivers seeking lower fuel consumption and emissions without giving up the convenience of an automatic.
The start-stop function cuts the engine automatically when the car comes to a halt and the driver holds the brake. The engine restarts as soon as the brake pedal is released, aiming to minimise idling in traffic. While start-stop had already become common on manual gearboxes, integrating it with an automatic, especially a dual-clutch system, presented extra engineering challenges. Audi’s S tronic manages this by monitoring brake input and transmission status, allowing for a quick and smooth restart.
Efficiency gains for diesel and petrol A3s
Audi’s initial rollout covers the A3 1.6 TDI and 1.4 TFSI, both offered as three-door and Sportback. The 1.6-litre diesel produces 77kW (105hp) and 250Nm, returning a claimed 4.2l/100km and 109g/km CO2. The 1.4-litre turbo petrol delivers 92kW (125hp) and 200Nm, with official figures of 5.3l/100km and 124g/km CO2. Performance remains competitive: the diesel reaches 100km/h in 11.7 seconds, the petrol in 9.3 seconds. Top speeds are 194km/h and 203km/h respectively.
Both models also include Audi’s energy recovery system as standard. The system charges the battery during braking and coasting, reducing alternator load during acceleration. This further trims fuel consumption, especially in stop-start urban conditions where both systems are most active.
Pricing and availability
Audi set the A3 1.4 TFSI S tronic at €23,700 for the three-door and €24,600 for the Sportback. The 1.6 TDI S tronic starts at €25,500 (three-door) and €26,400 (Sportback). Sales begin in November 2009. The addition of start-stop and energy recovery does not affect the price of the 1.4 TFSI, while the diesel with S tronic comes in above the manual equivalent.
Urban focus and future direction
Audi’s decision to combine start-stop with S tronic in the A3 reflects a broader push to cut urban emissions and fuel use. The technology is aimed at city drivers, where frequent stops allow the system to make the greatest difference. With rivals such as BMW and Mercedes also developing similar systems for automatics, the move signals the start of wider adoption across mainstream models.
For details on how Audi’s low-emissions diesel strategy developed, see Audi A3 1.6 TDI Cuts CO2 Emissions to 99g/km.
