The three-cylinder Ford 1.0-litre Ecoboost engine is to be offered with fuel-saving cylinder deactivation technology that will enable it to operate as a two-cylinder unit.
Similar technology is seen on many four-cylinder engines, but Ford claims this is the first time it has been engineered into a three-pot. Some manufacturers have dismissed the idea, citing refinement as one of the main issues, but Ford hasn’t been deterred.
Cylinder deactivation will automatically stop fuel delivery and valve operation for one of the engine’s cylinders under conditions where full capacity is not needed, such as when coasting or cruising with light demand on the engine. The technology can disengage or re-engage one cylinder in 14 milliseconds.
Capable of operating at speeds of up to 4500rpm, the system uses engine oil pressure to activate a special valve rocker and interrupt the connection between the camshaft and the valves of cylinder number one. Software uses factors including speed, throttle position and engine load to determine when to deactivate the cylinder.
The 1.0-litre Ecoboost - first introduced in 2012 - has a new single-piece camshaft module that has freed up space within the cylinder head for new oil channels and valve-switching componentry.
Ford engineers predict that the system will be active for a few seconds at a time in most driving scenarios and has the potential to improve fuel efficiency by up to 6%.
Installed in the current Fiesta, the 1.0-litre Ecoboost in 98bhp form is capable of a claimed combined economy of 65.7mpg, so a 6% improvement could take that figure to 69.6mpg.