Get smart and clean up

Nov 24 2008 Chris Russon

THE greenest diesel engined car ever produced will go on sale next year as smart cleans up its act in the city.

The diesel version of the smart fortwo is being dubbed the CO2 Champion with ultra-low emissions of 88g/km.

It makes the tiny urban runabout exempt from car tax and congestion charge and with a claimed average of 85.6mpg will be one of the cheapest cars to run.

Priced from £7,915 the smart cdi is said to be capable of returning 83mpg even around town which gives it a range close on 720miles.

For the average motorist that equates to a visit to the filling station only once a month.

While other auto makers have strived to bring in cars below the 100g/km tax threshold smart has simply fitted a lean burn three-cylinder diesel engine to its little two-door model.

Although its performance out on the open road will not set the world alight, it is surprisingly nippy in everyday use.

The 799cc diesel develops just 45bhp and has a top speed of 85mph with 0 to 60 acceleration of 19.8 seconds. On paper that makes it the slowest car on the market but such is the mid-range power of the engine it can hold its own on city streets.

The fortwo diesel will go on sale in March as part of an eco offensive already underway from smart and its parent company Mercedes-Benz.

Stop-start technology is being introduced on the fortwo - although not on the diesel - as well as on the Mercedes C-Class range and on some vans and trucks. Electric smarts are also under trial in London.

The mission is to cut fuel consumption by ten per cent - a huge saving, especially for commercial operators.

The smart stop-start is described as a micro-hybrid drive car.

Stop in traffic with your foot on the brake and the engine cuts out, restarting automatically as soon as the pedal is released.

It's not the smoothest of experiences and neither will it work if the handbrake is applied instead of holding the car on the foot brake.

The result is you have to have your brake lights illuminated when using the system - not exactly the kindest way of demonstrating your green credentials to the driver behind.

When I tried the system, the smart mhd seemed to get quite bothered in queuing traffic uphill - almost as if the transmission was going into spasm when moving off.

However, the system can be switched off via a button to the front of the gear lever.

The semi-automatic gearbox used by smart has improved significantly since its launch ten years ago but it is still not seamless.

It's best operated via the steering wheel mounted paddles - if fitted - but can still lurch through the gears unless you get the revs smack on when changing.

Emissions from the stop-start model are 103g/km with urban fuel consumption of 55.4mpg from the 71bhp, three-cylinder one-litre engine - an 11 per cent improvement over the standard smart.

Overall consumption is a claimed 64.2mpg, a 5.6 per cent improvement.

With the system fitted to the mid-range Pulse cabrio version of the fortwo it costs a basic £10,400, less than £200 more than the standard model.