GM says deceleration fuel cutoff in Cruze increases fuel economy by up to 2%
24 June 2011
The deceleration fuel cutoff (DFCO) technology applied in the Chevrolet Cruze increases the car’s fuel economy by up to 2%, depending upon specific driving conditions and behavior, GM said.
With DFCO, while the vehicle is decelerating or slowing down, fuel is automatically shut off to the Cruze’s Ecotec engine. When the driver accelerates, the fuel automatically begins flowing again and the vehicle accelerates as the driver commands.
On a single tank of fuel, DFCO technology contributes 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.
The Cruze is packed with fuel-saving technologies. 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.—Kai Loos, the development systems manager for the Cruze’s 1.4-liter turbocharged engine
DFCO is enabled when the driver’s foot is off the accelerator pedal and 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.
This technology is on Cruze models with both automatic and manual transmissions.
Chevrolet recently announced that for 2012, Cruze models with the 1.4L turbo and six-speed automatic transmission will get 2 mpg better fuel economy. 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. Cruze Eco with the standard six-speed manual transmission remains the most fuel-efficient gas-powered/non-hybrid vehicle in America, with an EPA-rated 42 mpg on the highway.
A 1998 Expedition (not what you would call an economy car) will disengage the torque converter clutch when the throttle is closed, to decrease drag -to coast better.
AND fuel is shutoff, when the throttle is closed, but only when speed is actually INcreasing (i.e. downhill).
We determined this with a Scangage-II.
More aggressive fuel shutoff brings some risk of barely noticable "drivability" issues.
Except for the very real risk of such barely noticeable irregularity, this is a really simple function and I believe in widespread use well before 1008.
Posted by: ToppaTom | 24 June 2011 at 04:32 PM
What is so special about this?
Every fuel injected engine that I have ever dealt with, has deceleration fuel cut! Some are more aggressive (and more annoying) than others, but they all do it.
Posted by: Brian P | 24 June 2011 at 04:38 PM
Come on. GM needs to be in the news.
Posted by: HarveyD | 24 June 2011 at 05:40 PM
So 24 mpg becomes 24.48 mpg...alert the media.
Posted by: SJC | 24 June 2011 at 07:26 PM
I can't believe they weren't doing this before??
Posted by: clett | 25 June 2011 at 09:40 AM