The updated 2014 Fiesta on sale next year will be the first vehicle sold in the United States with Ford's three-cylinder 1.0-litre EcoBoost engine. Though the car has not yet undergone EPA testing, it is expected to be certified as the most fuel-efficient non-hybrid car available in the US.

Adding an EcoBoost engine costs about US$995 in most Ford vehicles.

"Many customers would like the fuel efficiency of a modern diesel or a hybrid, but can't stretch their budgets to cover the cost premium," said Bakaj. "That's where the EcoBoost Fiesta fits in. It will offer a highly fuel-efficient alternative at a lower cost."

In Europe, the one-litre engine now accounts for about 30% of sales in the Focus. The engine is just now launching in the B- Max and C-Max, and will also be offered in the redesigned Mondeo (European Fusion).