Compared to its predecessor the new 2.0-litre CDTi engine offers an additional 7bhp and claimed improvements in efficiency. It now also complies with the incoming Euro-6 emissions standards which come into force in September 2015
The new 2.0-litre CDTi engine, which produces 168bhp at 3750rpm and 295lb ft from 1750-2500rpm, is also likely to be available in the new Astra when it arrives.
Key to the diesel's clean running is the addition of Selective Catalytic Reduction, included here under Vauxhall's "BlueInjection" banner. SCR technology involves using an AdBlue reducing agent to remove harmful NOx emissions from exhaust gasses.
Vauxhall is promising the new engine will be "among the very best diesels in its class". Noise and vibration levels are also claimed to have been reduced.
The release of this new engine forms part of a £3.2 billion Vauxhall plan to overhaul its powertrains, which will eventually result in 13 new engines being brought to market by 2016.
The 2.0-litre unit follows the release of new 1.6-litre petrol and diesel engines, as well as the 1.0-litre three-cylinder petrol powertrain which is available to order in the Adam supermini from this month.
Official economy figures will be revealed when the new engine is unveiled at the Paris motor show in October.
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