Seat has introduced a pair of new engines that markedly improve fuel economy and reduce emissions.
A turbocharged 104bhp 1.2-litre TSI petrol replaces the previous 1.6-litre of the same output in the Ibiza supermini range, with prices starting at 12,780 for an SE-specced car.
Fuel economy improves from 44.8mpg to 55.4mpg, while emissions drop from 149g/km to 119g/km. The cut in emissions earns the Ibiza a place in the cheapest 10% company car tax band and second-lowest VED band of 20 a year.
Performance is also improved, the 1.2-litre takes the Ibiza from 0-62mph in 9.8 seconds more than 0.5 seconds quicker than the 1.6 engine it replaces.
A 138bhp 2.0-litre common-rail diesel has also been introduced to the Leon, Altea and Altea XL ranges. This also brings better economy and lower emissions.
Average economy improves to 58.9mpg from 50.4mpg, while emissions fall from 147g/km to 125g/km. It is priced from 18,570 in the Leon.
Prices start at 18,770 in the Altea range for an SE car. Fuel economy improves to 57.6mpg while emissions fall to 129g/km.