With some relatively minor modifications, Volkswagen has extracted impressive fuel economy and emissions from its Jetta BlueMotion. High mileage drivers can save a packet with the 61.4mpg combined cycle showing and emissions of 122g/km should lessen the tax burden.

BlueMotion is Volkswagen's efficiency brand. Customers prioritising low fuel consumption and modest CO2 emissions can make a beeline for the BlueMotion Volkswagen models safe in the knowledge that they are the cleanest and greenest in their respective ranges. Here, we're taking a gander at the BlueMotion version of the Volkswagen Jetta saloon. The Jetta is a car that usually keeps itself to itself but in BlueMotion form, it has more to shout about.

Volkswagen might want you to believe otherwise but it hasn't done anything overwhelmingly clever with its BlueMotion models. There's no advanced hybrid powertrain humming away under the surface, you don't have to plug the cars in to charge before you go to bed at night and the dashboard is not constructed from recycled toxic waste. The manufacturer has made a series of small but telling modifications to its standard cars and the results are there for all to see.

The Jetta BlueMotion is powered by a 1.9-litre turbodiesel engine, not the most hi-tech in Volkswagen's portfolio. It generates 103bhp which translates into a sprint to 62mph from standstill in 11.9 seconds and on to a top speed of 117mph. It makes a very relaxed motorway car with reasonable refinement and a monsterous range between fill ups. All models are fitted with a five-speed manual gearbox as standard and with longer gear ratios in third, fourth and fifth gears, engine speed levels are lower while driving. These actions alone reduce consumption by about 0.2 litres per 100km and also increase refinement at speed. The turbocharger has also been revised to help improve economy.

One reservation I have about this car are the lower rolling resistance tyres which might make a small saving in terms of fuel consumption, but don't hang on quite as well as softer rubber through a set of corners. If that proved the difference between a near miss and a prang, I'm not sure I'd like that on my conscience.

"An example of working smarter rather than harder."

Like the standard Jetta models, the BlueMotion derivative keeps things quite low key. The keen-eyed will spot the BlueMotion badging on the grille and the boot but otherwise few would spot that this is anything but a stock Jetta. The modified grille, the flow-optimised underbody and the harder compound tyres aren't immediately obvious and the design details such as the low engine idling speed and the fitment of a diesel particulate filter aren't broadly publicised either. After all, is there anything worse than the overt and sanctimonious smugness of a typical hybrid car driver?

Otherwise, the BlueMotion is much like any other Jetta model. Viewed from the front, the Jetta is just like a Golf except for the chrome section inserted below the grille. Progress round to the rear though and the protruding boot will hove into view. Your take on this will depend on your perspective. In many European countries, the saloon bodystyle equals class and prestige in comparison to the shopping trolley hatch. Over here, the commonly held view is that it spoils the lines and the practicality of a perfectly good hatchback. Take your pick. The Jetta's interior is a little plusher than standard Golf fare, although the basic architecture of the dashboard is the same. The boot itself is large enough to make you question the need for a hatch at 527 litres. That makes it more capacious than the boot of a BMW 7 Series. For extra flexibility, the 60/40 split rear back-rest can be folded forwards to form an almost flat floor up to the front seats.

The BlueMotion Jetta comes with one specification which includes the basics like air-conditioning, electric windows, rain sensing wipers, remote central locking and a multifunction computer. In addition, buyers get the special alloy wheels shod with 205/55 R16 low rolling resistance tyres, a visual gear change recommendation, lowered sports suspension and a tyre repair kit to replace the full size spare wheel.

Somewhat perversely, the biggest threat to Jetta sales could come from the Passat which has its own BlueMotion derivatives. Volkswagen have pitched Passat prices rather aggressively and given that the Jetta carries a premium of around £1,000 over its Golf equivalent, the two booted cars could be uncomfortably close bedfellows in terms of price. Buyers wanting the extra space of the Passat may well feel inclined to trade up.

Whether the Jetta BlueMotion makes any sense to you depends on a number of parameters. Higher mileage motorists may well be able to recoup that premium back in terms of fuel economy, the BlueMotion's 61.4mpg comprehensively trumping the standard car's 54.3mpg showing. Then there's the taxation savings that the BlueMotion's 122g/km emissions generate.

Elsewhere things aren't so cut and dried. If you're a low mileage motorist, the standard car will appeal to more buyers. It's cheaper, it's a bit more fun to drive and customers are more used to it. Where the BlueMotion does claw advantage back is in terms of residual values. It's not inconceivable that a very strong demand will build for efficient used cars and BlueMotion owners will reduce their overall pence per mile running costs as a direct result.

What the Jetta BlueMotion and its BlueMotion brethren amount to is a standard Volkswagen car with a slightly modified diesel engine, low rolling resistance tyres, a longer ratio gearbox and some aerodynamic modifications. It sounds rather mundane but the results are anything but. 61mpg economy and 122g/km emissions are both impressive totals that allow owners to make genuine savings. Whether those savings are large enough to make the Jetta BlueMotion a worthwhile purchase will be dependent on your personal situation but either way, the BlueMotion is a useful addition to the Jetta range.

As an example of working smarter rather than harder, we doff our caps to the Volkswagen Jetta BlueMotion. No single aspect of this car's makeup is exceptionally clever, yet together a whole host of incremental efficiency improvements has resulted in a car that not only does the business in terms of emissions and economy but also makes a viable case for itself in cold commercial terms.