Those of you old enough to remember when Johnny Carson hosted “The Tonight Show” may also remember the comedian’s bit about the “Slauson Cutoff.” Well, a new piece of technology doesn’t require you to cut off your Slauson, but it does cut off fuel flow to save you gasoline when you’re decelerating. It’s called, imaginatively, deceleration fuel cutoff (DFCO).
When the vehicle is decelerating, fuel is automatically shut off to the Cruze’s Ecotec four-cylinder engine. In a conventional car, fuel would keep flowing and be essentially wasted in this mode. When the driver accelerates, the fuel automatically begins flowing again, and the vehicle accelerates as the driver commands. It’s a seamless process that the driver and passengers don’t notice, largely because they’re too busy thinking about themselves and those little worlds they live in.
The benefit is that the technology increases fuel economy in the Cruze by up to 2 percent, depending on specific driving conditions and driver behavior. That means on a single tank of fuel, this technology can contribute more than 17 miles of the overall range on the Cruze Eco model and more than 11 miles of range on the non-Eco Cruze models. While that may not seem like all that much, those essentially free miles can really add up over your ownership period.
“The Cruze is packed with fuel-saving technologies,” says Kai Loos, the development systems manager for the Cruze’s 1.4-liter turbocharged engine. “These types of cost-effective technologies allow Chevrolet to offer customers a vehicle that achieves hybrid-like efficiency -- without the cost of the hybrid technology.”
DFCO is enabled when the driver’s foot is off the accelerator pedal, when the vehicle is coasting. Through integration of engine and transmission controls, the engine speed is carefully controlled under these deceleration conditions. Fuel automatically begins flowing back to the engine when the driver accelerates or when the engine speed approaches idle conditions. Both automatic- and manual-transmission versions of the Cruze use the new technology.
For 2012, Cruze models with the 1.4-liter turbo and six-speed automatic transmission will get 2 mpg better fuel economy than similar 2011 models, and the Cruze Eco with an automatic transmission will deliver as much as 39 mpg on the highway, compared with 37 mpg for the 2011 model. The Cruze Eco with the standard six-speed manual transmission is the most fuel-efficient non-hybrid vehicle in America, with an EPA-rated 42 mpg on the highway.
