USA/Traffic jams could start to get quieter in 2012 when Ford begins to install its Auto Start-Stop technology on gasoline-powered cars sold in North America.

The technology, currently used on hybrid Ford vehicles, cuts off the engine when a car is stopped at a traffic light and switches it back on when the driver’s foot leaves the brake pedal.

Ford says Auto Start-Stop will improve fuel economy of conventional cars between four and 10 percent. And engine shutoffs will result in a reduction in greenhouse gas emissions. (In car-congested metropolises like Los Angeles and Houston, one could also expect to see a reduction in air pollution if the technology was widely adopted.)

Improvements in internal combustion engine technology allow cars to re-start instantly, according to the vice president of power train engineering at Ford, Barb Samardzich.

“The direct-injection system, which sprays the exact amount of fuel directly into the precise location in the combustion chamber, helps enable extremely fast engine starts,” Ford said in a statement. “The system includes a light on the dash that alerts the driver when the engine is off and a special tachometer that moves the needle to a green zone when the engine is not running.”