A higher-powered diesel option for Jaguar’s smallest model is set to play a key role in driving the ailing sports car manufacturer back to profit.

The turbo motor, an adaptation of the 2.2-litre unit just introduced in the Ford Mondeo, will form an important part of the strategy aimed at stemming massive losses at the Coventry firm.

Jaguar and Land Rover vice-president and chief operating officer Joe Greenwell said: ‘The X-Type is gathering in popularity as more examples are being seen on the road. This is an attractive range that will become more attractive still when we make it available in 150bhp turbodiesel form later this year. With this engine, the car is a flier.’

In an exclusive interview in Detroit after unveiling the Advanced Lightweight Coupe concept that is to be developed to replace the XK8 next year, Greenwell stressed that the car’s appeal to user-chooser motorists was vital to the plan to put the company back in the black.

"We made a mistake in 1999 when we assumed a growth strategy taking us to annual volume of 200,000 units. Much of that was based on the X-Type, which has in fact done very well and proved to be our star performer.

"But the target included assumptions for cabriolet and high-performance R versions that would give the range the derivative extensions of the BMW 3 Series and the Mercedes-Benz C Class –and that was over-ambitious, given the problems we had with resources.

"We went from two models to four, all with different architectures and all needing in-cycle freshening action, investment and engineering resource.

"And at the same time, we were also busy planning to build the XJ replacement in aluminium.

"There’s also no doubt that we underestimated our competitors and the rate of growth in the diesel segment. Happily, we are in a better position with diesel now and we will try to grow by offering the bi-turbo 2.7-litre unit in the XJ this year."

Greenwell revealed that exports to North America, which accounts for 40% of the company’s sales, have been cut and Jaguar has pulled out of the US fleet market. He said: ‘To do business in fleet, you have to apply significant incentives and I don’t want to be in that business – you don’t make money out of it and too much of that activity devalues the brand,’ he said.

He added: "However, if we can manage the supply properly, the opposite applies in the UK. I think we have the opportunity to succeed with user-choosers there as we strengthen the competitiveness of the X-Type."