Audi has reduced the CO2 emissions on its cleanest A1, bringing the rating down to 99g/km.
This German supermini drops its lowest rating from 105g/km, which brings free road tax and free entry to the London congestion charge area for the first time. The changes to the fuel system and engine management unit have also improved its economy, with consumption now at 74.3mpg from 70.6mpg.
The car retains the same start/stop system and energy recuperation capabilities as before, and the 1.6-litre diesel engine is otherwise unchanged. Because of this it retains the same performance figures, with 0-62mph taking 10.5 seconds and it managing a top speed of 118mph.
This engine is available with all three of the A1's trim levels – SE, Sport and S line – and it costs from £14,480 to £17,865.
The new engine is available to order from dealers immediately.