It seems like only a few years ago that diesel was unimportant to Ford.

They sold a few but they didn't make a song and dance about it.

But it's a sign of our changing motoring landscape that diesel is now central to just about everything that Ford does.

Not only is diesel, understandably, vital to the big-selling Mondeo models, it's also central to the sports versions of Britain's favourite company car.

Take this model, the £18,800 Mondeo TDCI which is powered by the 2.2 litre Duratorq engine. This was launched last August and is one of 18 diesel Mondeo saloons.

There are 25 diesel hatchback Mondeos and a similar number of the Mondeo estate, too. Who says only the French care about diesel cars?

The test version is one of the more capable and relatively expensive Mondeo saloons.

Mondeo itself should need no introduction. It's Ford most convincing mid-market saloon which enjoys tremendous loyalty, especially among fleet customers.

The saloon is not as popular as the hatchback but it is, in my view at least, a prettier car. It is well equipped, better built than any Mondeo to date and spacious.

The saloon also sheds more value than the hatchback, but if you're buying one you can expect a hefty discount, according to the people at What Car?

If there is a criticism of Mondeo, it's that it is just too successful.

There are so many of them around. Rather like the new MINI, every other car seems to be a Mondeo.

The new engine is one to be admired. It's a 2.2 litre unit which is smooth, powerful and refined.

Every diesel you read about these days is good but this is one of the best and it's been tuned to be good at low revs.

The ST models are sports models which come with the usual trim. It also has a lowered and firmed-up suspension.

You don't have to have the sports model to enjoy this engine, though. It's available on all Zetec models as well as Ghia, Ghia X, Titanium and Titanium X.

The Mondeo ST TDCi is exclusive to the UK and has been created to build on the popularity of TDCi in the UK, which accounted for 54 per cent of Mondeo sales in 2003.

Ford's overall diesel sales volume is up 27 per cent, with total 2003 sales of 86,016 and the top two positions in the diesel sales chart with Focus and Mondeo.

PRICE: £18,880 What Car? say £15,870 is possible.

ENGINE: A 2.2 litre unit generating 153bhp.

PERFORMANCE: Top speed 137mph, 0 top 60mph in 8.9 secs.

EMISSIONS: 151g/km.

COSTS: urban 34.5mpg; extra-urban 57.7mpg; combined 46.3mpg.

WARRANTY: Three years or 60,000 miles.

INSURANCE: Group 13.

All T&A road test vehicles are independently selected and assessments are carried out impartially by members of our own staff who base their opinions only on the vehicle supplied for these purposes by the manufacturer