New Audi A3 autos to feature start-stop techTechnology could cut CO2 emissions by 5g/km

20 October 2009

Start-stop technology is rare on autos

Start-stop technology is rare on automatics

Audi has announced two A3 automatic models that are available with start-stop technology. This combination is a first in the premium compact hatchback sector.

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In fact, the start-stop automatic combo is rare in any segment of the motoring marketplace. The new system is available on the Audi A3 1.4 TFSI turbo petrol and the 1.6 TDI turbodiesel.

Start-stop systems

Start-stop systems that work with manual gearboxes require the driver to place the car into neutral before the engine automatically switches off. Since this is impractical in an automatic, Audi requires only that the car be at a standstill and the brake pedal depressed.

It takes just two-10ths of a second for the A3 to restart after the brake pedal has been released. Sounds simple and straightforward to use, if unfortunate that there is no way to avoid dazzling the drivers behind you with your brake lights. It can be deactivated if required.

So far, Audi’s system is only available with the company’s twin-clutch S tronic automatic. This offers both smooth, fast shifts and impressive economy.

Eco benefits

Audi claims start-stop reduces real world CO2 emissions by around 5g/km, while the additional inclusion of brake energy recuperation technology - energy that would otherwise be lost when the car is braking is recovered and stored in a battery then released to reduce strain on the engine when next accelerating - reduces fuel consumption by up to 3%.

As a result, the A3 1.4 petrol automatic start-stop returns 53.3mpg and emits 124g/km CO2. That’s a useful improvement over the manual version, which manages 49.6mpg and 132g/km. 0-62mph takes 9.3 seconds, 0.1 seconds faster than the manual.

Figures for the 1.6 TDI start-stop auto are 67.3mpg and 109g/km CO2. In this case the manual does slightly better with 68.9mpg; it emits the same level of CO2.

Pricing for the 1.4 begins at £18,300, while the 1.6 TDI starts at £18,905. Both are available to order now, and arrive in showrooms December.


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