The updated Audi A1 1.6 TDI now emits just 99g/km of CO2.
Tweaks to the fuel system and engine management have dropped CO2 emissions from 105g/km, while average fuel consumption is boosted from 70.6mpg to 74.3mpg.
As before, engine stop-start and energy recuperation systems help to make it as fuel-efficient as possible.
With CO2 emissions dipping below 100g/km the A1 1.6 TDI is now exempt from the London Congestion Charge. Buyers also don't have to pay Vehicle Excise Duty (VED), saving £20 per year compared with the previous 1.6 TDI, which was duty-free in the first year of ownership only.
Prices for the Audi A1 1.6 TDI are unchanged. They start at £14,480 for the SE and rise to £17,865 for the S line model.
Read the full Audi A1 review
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