The new technology achieves the seemingly impossible feat of boosting power while improving fuel consumption and reducing carbon dioxide emissions.
The CO2 emissions of the A4 2.0 FSI are 170g/km, 20g/km lower than the standard A4 2.0, while the new engine's fuel economy has improved by about 5mpg and power by 20bhp.
The 2.0 FSI engine carries a £1,000 premium over the standard 2.0-litre model, costing £19,565 on-the-road for the saloon and £20,695 for the Avant. However, despite its higher price, the improved emission of the FSI put it two tax bands lower under the new benefit-in-kind tax system, delivering a tax saving of about £100 a year for a 40% payer.
The direct injection petrol engine works in a similar way to common rail diesels by injecting fuel at high pressure directly into the cylinder, rather than into the intake manifold as on most petrol engines.