New 1.5-litre TSI petrol and TDI diesel engines will replace existing 1.4 and 1.6 motors in cars like the VW Golf and Skoda Octavia

Volkswagen will roll out a new line-up of four-cylinder petrol and diesel engines over the next couple of years, replacing the existing 1.4-litre and 1.6-litre motors with 1.5-litre units across the range.

The new, more efficient engines are designed to comply with even stricter emissions regulations due to be introduced in 2020. The 1.5-litre turbocharged petrol will replace the turbocharged 1.4 TSI that’s used in cars like the VW Golfand Skoda Octavia; it will make its first appearance in the facelifted version of the Mk7 Golf, due before the end of this year.

The diesel replaces the VW Group’s venerable 1.6 motor - although its introduction will be phased in around a year after the petrol’s. It will make its debut in the facelifted Audi A3, but close to the end of that car’s life, in late 2017. It is unlikely to appear in the Mk7 Golf; it’ll be phased into the Mk8 instead.

“The installation of the engine in cars like the Golf and A3 is very straightforward,” said a high-level VW source. “The engines are all new but their dimensions are very similar to what we currently use, so they can slot into existing cars or facelifts.”

Volkswagen Golf Mk8 - front

The Golf Mk8 won’t appear until 2018 but along with the new 1.5-litre petrol and diesel engines, we can also expect the hatchback to shed between 35kg and 70kg of weight while at the same time being lower and wider than the outgoing model.

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