Audi is launching its luxurious all-alloy A8 saloon this month with stop-start technology - becoming Australia's first car with a full-automatic transmission to use the fuel-saving feature. It will be standard only on Audi's 3-litre V6 turbo-diesel model that has an eight-speed Tiptronic automatic.
Bosch, which makes the stop-go system and to date has produced 1.5 million units, says that in a full automatic, it can save up to 8 per cent of fuel by automatically turning off the engine when the car is stationary. The engine restarts simply by the driver taking pressure off the brake pedal.
Audi isn't alone. BMW Australia says the new X3 SUV, expected here early next year, will be the first fully-automatic petrol fuelled car with the fuel-saving feature. Currently, some car makers offer stop-start only in models fitted with manual transmissions.
This month, BMW introduced its M3 range with stop-start, including the dual-clutch automatic models. "Technically, the M3 has an automated manual gearbox and unlike the X3's full-auto with torque convertor," says BMW Australia spokesman Piers Scott.
Bosch has made stop-go systems for the DSG transmission of the Volkswagen Passat and Porsche Panamera, the Fiat 500's automated manual, and the conventional torque convertor of the Audi A8 diesel. Bosch claims the stop-go system in an automatic transmission will reduce fuel consumption and CO2 emissions by up to 5 per cent on the highway and up to 8 per cent in the city.