Stop-Start Technology shuts down the engine when the car makes a complete stop, than restarts it immediately once the driver lifts the foot off the brake pedal (on automatic gearbox cars) or engages the clutch (on manual transmission ones).
The system from GM is called eAssist and will be fitted as a standard feature on all 2012 versions of the four-cylinder engine powering the Buick LaCrosse sedan. The system will be available as an option for the 2012 Buick Regal.
This kind of technology is already used by Mercedes-Benz, BMW, Porsche, Mazda, Peugeot, and, in the next few years, Ford intends to introduce a similar system for its models.
"We call this a 'light electrified' technology, and it provides a lot of bang for the buck in terms of overall cost, compared with full hybrids," said Steve Poulos, chief engineer for eAssist.
"It could become our base powertrain," he added.
According to Poulos, the 2.4-liter eAssist engine with a six-speed automatic transmission on the LaCrosse model will be capable of achieving 25 mpg (9.4 liter/100 km) when driving around in the city and 37 mpg (6.3 liter/100 km) when cruising down the highway. The eAssist system manages to achieve a 25% fuel efficiency improvement over the 2011 LaCrosse model.
Fuel injection is featured on General Motor’s eAssist engines, which allows the power unit to activate in just 200 to 300 milliseconds. A 115-volt lithium-ion battery and a 15-kilowatt motor-generator come in addition to the 180 hp gasoline engine.