Ford Authority

All-New, 2018 Ford Fiesta ST To Feature Cylinder-Deactivation

With its turbocharged, 1.5-liter three-cylinder engine, the all-new, 2018 Ford Fiesta ST unveiled ahead of the Geneva Motor Show in Switzerland this month, is down by one cylinder – and approximately 100 cubic centimeters – versus the outgoing hot hatch.

But Ford’s attempts to cut down on the subcompact hotrod’s fuel consumption haven’t stopped there; like the improved 1.0-liter EcoBoost three-cylinder available in the non-ST models of the 2017 Fiesta, the 1.5-liter EcoBoost powering the new Fiesta ST will feature cylinder-deactivation technology. This will allow the car to “turn off” one of the engine’s three cylinders in certain conditions, effectively turning the engine into a more fuel-efficient two-cylinder temporarily.

That sort of mindfulness of emissions may seem at odds with the Fiesta ST’s sporting aspirations, but the good news is that Ford’s cylinder-deactivation is capable of operating very, very quickly, with the middle cylinder deactivating or reactivating in just 14 milliseconds. And as with all such systems, it will only kick-in while the car is maintaining a somewhat-steady cruising speed in a high gear.

We’ll have to wait in order to find out just how much fuel is saved, and how much CO2 kept out of the atmosphere, by Ford’s new performance-oriented, 1.5-liter EcoBoost I3. But cylinder-deactivation – along with one fewer cylinder, dual-injection, and a more sophisticated turbocharging system – ought to help the 2018 Ford Fiesta ST run greener than the hot hatch it replaces.

Aaron Brzozowski is a writer and motoring enthusiast from Detroit with an affinity for '80s German steel. He is not active on the Twitter these days, but you may send him a courier pigeon.

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  1. jody

    Being limited to the choice of a 3-cylinder engine will result in my choosing to not lease another Fiesta ST when my current lease is up.

    1. Jim

      Why? The same power output in a lighter, more economical, more MPG car? I’m just curious what is wrong with that? Newest technology is a good thing.

      1. jody

        My interest is in performance. I got a FiST because it’s a sharper tool. I want my next one to be sharper still, not dulled by the removal of a cylinder.


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