VW's 1.5 TSI ACT BlueMotion gas engine is as efficient as a diesel

VW has announced a new engine that it says is as efficient as a diesel engine. The new engine is called the 1.5 TSI ACT BlueMotion and it uses variable turbine turbo technology from high-performance sports cars. One key feature of the engine, which will be used in the Golf, is that the engine can deactivate cylinders or completely turn off when needed for efficiency.

The tech allows the gas engine to offer the sort of fuel economy previously only found with a diesel engine. The engine has a power output of 130 PS and is already powering some Golf models. VW notes that it plans to make the same 1.5 TSI ACY BlueMotion engine available for other VW models.

The engine offers combined fuel consumption of 4.8L/100 km. NEDC extra-urban fuel economy is 4.0L/100 km. VW says that he new engine is 10% more fuel efficient than comparable gas engines. Some of the economy benefits of this engine come from the TSI Miller combustion process.

The engine is particularly efficient when driven in partial load range. The two inner cylinders can be deactivated when power demand is low. Deactivation can happen between engine speeds of 1400-4000 rpm and at vehicle speeds up to 130 km/h.

Eco-coasting mode works with the 7-speed DSG gearbox and allows the driver to coast when going down a slope. In that mode, the engine switches off when the accelerator pedal is released. That allows the car to switch into zero emission mode for brief periods. A micro-hybrid system uses a 12-volt electric system and a compact lithium-ion battery to supply vehicle systems when the engine is off.