Audi Cylinder on Demand Technology Increases Fuel Economy

By | November 12, 2013
Cylinder deactivation technology has been around for some time, but only recently has it made its way into the vehicles on the road today. Audi's "cylinder on demand," the automaker's take on this fuel-saving technology, has managed to cut fuel consumption by up to 20 percent in models that feature this system. Currently only three engines have this function, including the 1.4 TFSI COD and 4.0 TFSI COD, as well as the W12 COD, which is available on the Audi A8 L. The luxury automaker has made this technology versatile enough to use in the majority of its engine options, from the four- and twelve-cylinder direct injection unit to the V-8 TFSI engine. Half of all cylinders are deactivated at low to intermediate loads, and the engine speeds in the upper gears until the driver accelerates. Switching between activated and deactivated gears is smooth and will generally not be noticed by the driver. The engine closes the valves with cam elements that are shifted on the camshaft by electromagnetically actuated pins. Looking at the Audi RS 6 Avant with the 4.0 TFSI COD, this technology has shaved off 5 percent of fuel consumption, which pushes gas mileage up to 24 mpg. Models using the 1.4 TFSI COD like the A3 can get up to 50 mpg, saving roughly 0.4 liters per mile. Depending on the driving style of the owner, fuel savings can reach 20 percent.
Source: Audi