Mercedes-Benz C220 CDI 2006 Review

Running for the plane (late again!), I nearly forgot to check the final figure. After grabbing the keys back from the friendly crew at Qantas valet parking, I kicked the little Benz back into life, the now-familiar rattle quite strident in the enclosed space. Scrolling through the C-Class' trip computer the all-important number was 5.3lt/100km. DTE (distance to empty) was still reading 60km.

We'd easily done the Melbourne-Sydney trip on one tank of diesel. What's more we'd also spent a day at either end, fighting with city traffic -- on the same tank. Unlike some manufacturer's at times laughable claims, this economy -- better than 50mpg in the old scale -- was real-world.

As regular readers will attest, this diesel dunce is sounding like a broken record, but there's very little reason why we Aussies shouldn't run our four-wheel lives on distillate. Yes, the pumps themselves are often dirty (a box on disposable plastic gloves will fix that) and, yes, few diesels are exactly exciting to drive (though that's changing too), but the day-to-day economic benefits of the modern compression ignition engine cannot be ignored for too much longer. Even when diesel is priced at a premium (talk me through that!)

Mercedes has a long history of diesel passenger cars but SUVs aside locally it has kept a remarkably low profile in the current 'rebirth' of diesels. After all, taxis and executive transport alike, a decent wedge of Europe rolls along on diesel Benz wheels. Down Under, the company has in truth offered diesel sedans and wagons on and off for the better part of four decades.

As this is written, the C 220 CDI is the sole mid-sized diesel offered locally by Benz. Both A and B-Class diesels are available in Europe, as is the C-Class wagon. With Audi already offering a diesel A4 (and with 3.0-litre TDi A4 on the way) and BMW set to debut both 1 and 3 Series diesels, can we expect Mercedes to increase its oiler offerings? We'd say so.

That said, at this stage, the maker projects just four out of every 100 C-Class buyers will opt for diesel. After our interstate drive, we'd happily be one of the four.

In chassis and accommodation terms the C 220 CDI is indistinguishable from its four-cylinder petrol C-Class siblings.

Offered in a choice of Classic, Avantgarde and Elegance trim levels, it is priced a couple of thousand dollars above, the C 200K -- arguably the closest petrol C in terms of engine output.

Our tester, un-optioned Classic (metallic paint aside), was far from a stripper and a pleasing blend of sporty tones and luxury features. If nothing else, we liked the de rigueur all-black leather interior -- in our experience C-Class' have terrible trouble with dashboard/windscreen reflections in the light colour dashed Elegance models.

With little to distinguish the diesel in terms of trim or spec, this is very much an impression of the CDI's 2.2-litre four-cylinder powerplant. A willing mill, it is at times a touch coarse. Indeed, there's certainly no mistaking it's a diesel -- and one that's a touch more clattery than even VW/Audi's 'Pumpe-Düse' 2.0-litre four.

Perhaps that's forgivable given the vintage of the engine -- it's not the newest oiler on the block. Indeed, the current 220 CDi engine has been in use since the C-Class was released in 2001. Even then it was developed from the outgoing 2.2-litre diesel.

Since then Benz's engineers have refined the powerplant and incorporated q variable geometry turbocharger and the electronic common-rail fuel-injection to deliver an engine that produces 110kW at 4200rpm and a solid 315Nm of torque from 1800-2600rpm.

According to Mercedes-Benz, the current incarnation is both quieter and cleaner than the engine it replaced with fuel consumption on par.

As noted above, it's not short on tractive effort and is at its very best on the open road. Its 0-100km/h time of 10.5sec is nothing to write home about (1.1sec slower than the C 200 K for instance) but overtaking performance from, say 100km/h, is energetic and very probably better than its petrol stablemate.

The CDI's engine is matched to a five-speed automatic with Touchshift manual mode. The transmission is the same unit fitted to the petrol four-cylinder C-classes with ratio changes to first through third gears.

To account for the torquey, lower revving nature of the diesel (the petrol C 200 K's 120kW arrives at 5300rpm with peak torque of 240Nm from 3000-4000rpm), the diesel C gets a significantly taller (differential) final drive ratio -- 2.87 versus 3.147.

This sees the mid-sizer ticking over at well under 2000rpm at the Aussie open road limit.

For our Melbourne-Sydney trip -- up the Hume with a couple of detours -- we set the cruise control at 115km/h and let the car do the rest. No coasting and no silliness were required to register the 5.3lt figure. Indeed, we probably could have bettered the number if it wasn't for a dinner appointment in Sydney that saw the cruise speed upped a little more in the last couple of hundred km into the Harbour City.

The C's firm but supportive front seats delivered day-long comfort and unlike some of its direct competitors there was enough storage around the cabin for mobiles phones and the like.

Noise levels are subdued on the open road, but unlike, say, BMW's 3.0-litre six, you're unlikely to ever forget you're driving a diesel. Except that is when it comes to refuel -- our auto CDI's actual fuel consumption was better even than Benz's own claim of 6.3-6.5lt/100km (mixed urban and highway, manual trans) and 2.1-2.4lt/100km better than the claimed mark for the C 200K.

Overall, it was an absolutely fuss-free trip though the highway drone did show up an incongruous lack of cupholders. A modern car without cupholders? Our quick food and coffee stops had us nursing our beverages for the next few miles each time.

We know from our experience with petrol models, the latest C is a much more wieldy car than its predecessor. Around 40kg heavier, the CDI is no different. Still, the little Benz is still not on a par with its main competition from Bavaria. Steering lacks the feel of the 3 Series (even in latest E90 guise) though it is better than the lifeless helm of the A4. On the plus side, ride is better than both, though the Beemer arguably still pips the Benz in terms of body control and outright grip.

As one of the few remaining midsize rear-wheel drive platforms, we'd like to see Mercedes take advantage of the C and give it just a touch more sporting ability... And yes, that even includes the diesel version!