It seems like such a simple idea: when a car is idling while stationary, it returns zero mpg. Turning off the engine while stopped helps save fuel, and has led to the increasing adoption of engine stop-start features, which automatically shut off a car’s engine when it is stopped in traffic. According to the Automobile Association of America, those engine stop-start systems will be present on as many as eight million cars across the country in just five years’ time.
Engine stop-start functions first debuted on hybrid cars, which could switch off the gasoline engine to temporarily drive on electrical power. More recently, however, automakers have added engine shutdown functions to non-hybrid cars. In the U.S., those systems are available on non-hybrid cars from Mercedes-Benz, Porsche, BMW, Jaguar, and Kia. The 2013 Ford Fusion will offer stop-start as a $295 option, and even the 2013 Ram 1500 pickup truck will implement stop-start on its V-6 model.
According to AAA, stop-start technology is already available on 40 percent of new cars sold in Japan and Europe, where it has been more widespread for several years. Here in America, the group estimates that stop-start features could save the average motorist about $167 in fuel each year. Ford predicts that its stop-start feature will reduce fuel consumption anywhere from 3.5 to 10 percent in city traffic.
That’s not to suggest engine stop-start systems are all good news. When we sampled a 2012 Kia Soul with an early version of the company’s Idle Stop & Go technology, we found the system “surprisingly crude.” Similarly, our Four Seasons 2012 BMW 328i continues to receive criticism of the harsh vibrations that occur when the stop-start system activates.
What do you think: are engine stop-start systems the way of the future? Do the fuel savings make it worth tolerating additional engine vibrations and a higher price tag, or should automakers focus on true hybrids and electric cars? Sound off in the comments section below.