The new A4 comes with three engine options, the potent 3.0-litre V6 diesel, the staple 2.0-litre diesel, and the base 1.8-litre petrol, which we have tested here. This direct-injection, turbocharged motor was also present in the old car, but has now been significantly revised. With the upgraded engine comes better performance, driveability and emissions. The key changes lie in the cylinder head – it’s now got two injectors per cylinder, one for direct and the other for indirect injection. The direct-injectors work at startup and with big throttle inputs, while the port injectors work under periods of low loads and speeds, and this helps improve particulate emissions and fuel efficiency.
The improved driveability is thanks to an electronically controlled turbocharger wastegate that responds faster and quickens the engine’s response to throttle inputs. This engine now makes 168bhp (10bhp up from the old engine) and a healthy 32.6kgm of torque all the way from 1400rpm to 3700rpm.
The transmission is not the expensive twin-clutch gearbox that’s almost de-rigueur on Audis these days. What it does have, though, is an eight-step continuously variable transmission that sends power to the front wheels – a combination that works in unexpectedly entertaining ways.