Audi Cylinder on Demand

A system that temporarily deactivates half of the cylinders to help decrease fuel consumption by closing engine valves.

A long stride in fuel efficiency. At low and medium loads, the cylinder-on-demand system temporarily deactivates half the cylinders in the engine by closing engine valves to save fuel in coasting and lower acceleration scenarios. If the driver accelerates quickly, it switches back instantaneously to all cylinders to provide more power.