A few years ago, some automakers began offering stop/start technology on select cars as a way to help lower emissions and increase fuel economy in busy city traffic.
Early stop/start systems in non-hybrid cars were often slow to respond to driver input, making them unpopular with drivers, but now Ford claims to have solved some of those issues in its 2013 Ford Fusion’s optional stop/start system.
Ford says it has filed over 25 patents in developing the 2013 Fusion’s $295 optional extra, and is confident that it has developed a much more usable stop/start solution.
Traditionally, a stop/start system works by stopping the car engine when the driver presses the brake pedal, switching off the engine completely when the car is stopped. It then restarts the engine when the driver releases the brake pedal to move off.
Although it isn't technically a stop/start system, hybrid cars like the 2012 Toyota Prius use a powerful electric motor can provide instant torque to both start the car moving and start the engine. As a consequence, hybrid cars can stop the engine when stationary, but move away very smoothly and quickly when the brake pedal is released.
2013 Ford Fusion
2013 Ford FusionEnlarge Photo
In non-hybrid cars with stop/start however, the car’s engine has to be spun up to speed by the starter motor before the car can move. This can result in a juddering lag between the driver requesting power and it being delivered.
Less smooth than a hybrid drivetrain, automakers are striving to give gasoline cars without hybrid drivetrains the same smooth stop/start experience that hybrid cars have.
Ford’s new stop/start system utilizes a more powerful 12-volt starter battery, an upgraded started motor and an extra transmission pump that maintains gearbox hydraulic pressure even with the engine off.
It also uses new software to monitor and maintain battery voltage to ensure that the car can start cleanly and quickly when required, as well as a smart climate-control system that can start the engine early if the cabin gets too hot or too cold.
Ford claims the system will help improve the 2013 Ford Fusion’s fuel efficiency by 3.5 percent, although as it fairly admits, the biggest influencing factor in gas mileage is the driver.
Is Ford’s stop/start technology better than its competitors?
At the time of writing, we haven’t had a chance to test Ford’s claims, but as soon as we get behind the wheel, it’s something we’ll make sure we include in our first drive report.