Ford's fuel-saving technology that automatically shuts off the engine when the vehicle comes to a stop will soon be added to conventional cars, crossovers, and SUVs in North America. The Auto Start-Stop system will improve fuel economy 4 to 10%, depending on vehicle size and usage, according to the company. It can also reduce tailpipe emissions to zero while the vehicle is stationary or waiting at a stop light. Start-Stop requires no changes to the driver's behavior. In city driving when the vehicle is stopped, the engine restarts the instant the driver's foot leaves the brake pedal. When the engine is off, all of the vehicle's accessories function normally. A light on the dash will alert the driver when the engine is off. "For the driver, Ford Auto Start-Stop provides extra fuel efficiency without inconvenience, as it works completely automatically," said Barb Samardzich, Ford Vice President of Powertrain Engineering. "And, just like in our hybrid vehicles, the heater and air-conditioner work as normal so drivers will not sacrifice comfort." The fuel-saving system debuts in North America in 2012 and eventually will be offered in all of Ford's global markets. Some North American customers are already familiar with it since a similar system has been installed on more than 170,000 gasoline-electric hybrid vehicles Ford has sold since 2004. Auto Start-Stop will be available on gasoline-powered cars and utilities with either a manual or automatic transmission as well as vehicles that use Ford's dual-clutch six-speed automatic transmission.