What is it?
Britain's road tax system doesn't reward drivers for choosing the most efficient car possible once below 100g/km. But the EU CO2 range emissions target means there's an incentive for car makers to eek out the last drops of carbon dioxide efficiency from their models. As Britain's best-selling car, the benefits of the greenest Fiesta having its emissions slashed are manifold.
The Fiesta Econetic now emits 87g/km, down from 95g/km and records an official 85.6mpg on the combined cycle. The previous Econetic covered 78.5mpg. The most obvious change is the introduction of automatic start-stop, the first Fiesta to have such a system.
The Fiesta has longer gear ratios for third, fourth and fifth gear with an unchanged final drive. The 1.6-litre TDCi engine has a redesigned injection system with improved eight hole injectors controlled by a more powerful engine management system. The air-conditioning, cooling fan and alternator are all more efficient than the outgoing model.
What's it like?
The result is an engine that feels much the same as the old car. Start up from cold is lumpy, and while vibration is absent, the four-cylinder's thrum is intrusive under load. It's a flexible engine, capable of pulling from fairly low engine speeds. There's enough kick to make untroubled motorway overtakes, but ultimate motorway efficiency and refinement is hampered by the lack of a sixth gear.