It's no clever trick these days to shut off a handful of cylinders in large engines, and it's a good way to curb excessive fuel consumption when big power isn't needed.
Now, German giant Volkswagen has emerged as the first major manufacturer to utilise cylinder deactivation in a four-cylinder engine.
Scheduled for a market debut in 2012, Volkswagen's new 1.4 litre TSI engine will deliver a 0.4 l/100km reduction in fuel consumption, thanks to cylinder deactivation. Adding a stop/start system will cut a further 0.2 l/100km of fuel use.
In the new engine, cylinders two and three will be shut off when the engine speed, under constant throttle, is between 1400 and 4000rpm, and torque between 25 and 75Nm.
According to Volkswagen, that's 70 percent of the European fuel economy driving cycle.
When acceleration is detected, the fuel delivery to the shutdown cylinders is resumed, and Volkswagen promises an undetectable transition.
For those that enjoy a spirited drive in the countryside, a sensor can also recognise a "nonuniform" driving pattern, temporarily switching off the cylinder deactivation system to accommodate the more demanding excursion.
It's unclear at this stage which vehicles will get the new engine, but in standard form, the current 1.4 TSI engine is offered internationally with the Golf, Tiguan, Jetta and Scirocco - among others.