Saab 9-3 diesel driven

What is it? Saab 9-3 with new low-CO2 diesel engine.
Price: £22,995 to £27,055
On sale: Now

Saab describes its new 119g/km 9-3 diesel as a 'skunk works' project.

A small core of engineers continued to develop the car even as the factory shutters were being pulled down by Saab's General Motors.

Now under new ownership, the project has produced this, the most tax-efficient 9-3 to date.

Saab has managed to get under the 120g/km mark, but not just with its lower-powered diesel model. All three diesels, with 128bhp, 158bhp or 177bhp, manage 119g/km, which equates to claimed economy of 62.8mpg.

Saab has gone straight to the head of the pack in the power-to-CO2-output ratio. A 187bhp 2.7-litre Audi A4 emits 167g/km, a BMW 320d with 181bhp produces 125g/km, while the 168bhp Mercedes-Benz C220 emits 127g/km.

These rivals are also more expensive than the 177bhp version of the 9-3, which costs between £22,995 and £27,055.

What's changed? What's the benefit?
All three versions of the engine have two turbochargers rather than one. The engine's control software has also been tweaked, the gearing has been changed and there are low-rolling-resistance tyres.

There are more efficiency gains: the brake pads spend less time rubbing the discs to dry them, the alternator disengages to reduce parasitic losses and there are some aerodynamic tricks underneath the car to improve airflow.

The car is also 50kg lighter than before thanks, in part, to the use of new sound-deadening material and smaller brake discs.

Company car drivers benefit from the lowest (13%) tax rate, which cuts hundreds of pounds from the 2010/11 tax bill. Getting below 120g/km also means companies can write down 20% of the car's value rather than 10%, however, and fuel bills should also be smaller.

What's it like to drive?
Long gearing can often make low-CO2 cars laborious to drive because you often have to shift down to overtake or keep up with motorway traffic.

Sixth gear in the 9-3 is best-suited to those all-too-rare occasions when the traffic flow on UK motorways moves consistently at the national speed limit, but the 177bhp version has 295lb ft of torque and so pulls okay from 60mph.

There's a slight pause in low revs before the engine comes on song, but it doesn't bog down.

The gearshift isn't great, though. It's a bit notchy, the throw is long and the lever is placed quite far back, making shifts tricky.

The abilities of the engine also can't make up for the 9-3's shortcomings.

Yes, it's well-equipped spacious and safe, but the quality of the cabin materials isn't good enough. The plastics, upholstery and switchgear all need to take a leap forward if Saab wants to entertain the idea of being a quirky alternative to Audi, BMW and Mercedes-Benz.

While engine noise isn't an issue, the amount of wind noise generated around the door mirrors is too great at higher speeds, and poor surfaces quickly unsettle the ride.

More steering feel would also be welcome, and the 9-3 isn't as fun to drive as its rivals. Considering the poke of the engine, this is a shame.

Is it worth it?
There's no denying the 9-3 is different, but it's also off the pace in a super-tough competitive class of cars.

While it can now compete with rivals on CO2, it falls behind them in too many other areas.

The updates help the car, but it's the all-new model in 2012 that we're looking forward to and which Saab has to get spot on.

What Car? says