Honda Accord i-CTDi Executive

The firm can hold its head up high against any brand which is perceived as more prestigious, except in one area - diesel technology. With oil-burners accounting for up to three-quarters of some European rivals' sales, Honda did not have a hope of real success without a decent turbodiesel model.

We've already been impressed by a brief drive of a prototype oil-burning Accord, so when the finished car arrived, we decided to put it to the ultimate test - head-to-head with the class-leading BMW 320d.

Apart from the badge on the rear and the new front foglights, there aren't any significant visual differences between the derv-powered Honda and its petrol equivalent. But can you tell the difference from the driver's seat?

The Achilles' heel for any diesel is the characteristic clatter and vibration on start-up. Turn on the new Accord, though, and you are barely aware of what's in the tank unless you listen hard. Thicker glass in the front windows and extra sound deadening make this Honda one of the quietest oil-burners at idle, and little changes on the move. The normal derv noise is replaced by an unusual whirring, but most passengers will still presume they're in a petrol car.

And to extend the illusion, the Accord has a self-adjusting clutch which allows optimum performance without a need for owners to alter their driving style to suit a diesel's power delivery. As a result, this vehicle even behaves like a petrol car, making Volkswagen's laggy PD TDI feel dated. And it certainly teaches the 3-Series a thing or two about refined engine output.

Peak power for the new Accord unit is 138bhp against the 320d's 150bhp. But torque is what counts for diesels, and the Honda's 340Nm betters the BMW by 10Nm. Despite the benefit of all that pulling power, the Accord is left behind by its key rival in the 0-60mph sprint -hitting the mark in 9.4 seconds compared to the 320d's 8.8 seconds.

Equally high on the priority list in this market sector are fuel efficiency and emissions, and the Honda is predictably frugal. Between visits to the black pump, the Accord returns 52.3mpg - 2.7mpg better than the 320d - and pumps out 142g/km against the BMW's 153g/km.

With the Beemer set to clean up its emissions from September, both models will be compliant with stringent new European regulations, which means they both bypass the usual three per cent levy on company car tax which afflicts dirtier diesels. Move on to prices and Honda buyers will have another reason to be happy. Although no official figures have been confirmed, the i-CTDi is only available in Sport and Executive trim, and is set to cost around ΂£1,200 more than the petrol version. However, it does gain vehicle stability control as standard.

That places entry-level oil-burning saloons at about ΂£18,700, with the top-of-the-range estate at around ΂£21,200. The Executive model seen here looks set to weigh in at ΂£20,200, undercutting this 320d ES by ΂£795. What's more, the Accord's bulging list of standard kit puts the ES to shame, although BMW is currently offering a valuable five-year, 60,000-mile free servicing package on all diesel 3 and 5-Series models.

So which is the better choice? With a reputation as a builder of top-class engines to uphold, it was vital Honda produced a class leader - and the company hasn't let us down. If pure driver enjoyment and brand image are your priorities, the swifter rear-wheel-drive 3-Series might just edge it. But for the rest of us, the cheaper, better-equipped, quieter and more economical Accord i-CTDi will be the model to go for.