Mercedes-Benz 250 CDI 2013 Review

Price Guide (recommended price before statutory and delivery charges): $96,400 E 250; $98,900 E 250 CDI
Options fitted (not included in above price): Metallic Paint $2100; Vision Package $5500 (includes digital radio DAB+, glass sunroof and Harman Kardon Logic 7 audio)
Crash rating: Five-star EuroNCAP (based on 2010 model)
Fuel: 95 RON PULP (E 250); Diesel (E 250 CDI)
Claimed fuel economy (L/100km): 6.4 (E 250); 4.9 (E 250 CDI)
CO2 emissions (g/km): 148 (E 250); 129 (E 250 CDI)
Also consider: Audi A6 (from $77,900); BMW 5 Series (from $78,500); Jaguar XF (from $68,545); Lexus GS (from $77,045)

The trend to fitting small but efficient engines in large cars seems like a recent one, but Mercedes-Benz has been doing precisely that for at least three decades.

From the late 1970s, the W123 Mercedes-Benz offered engines ranging in size from two to three litres, with most displacing less than 2.5. Nearly 30 years later the current W212 E-Class still offers a selection of fuel-saving engines promising driveability.

Recently motoring.com.au tested back to back a petrol E 250 and diesel E 250 CDI -- both cars positioned in the middle of the E-Class range.

Even though they were trimmed to the same level and with the same options, the piano-gloss black and little touches of bright metal trim here and there couldn't leaven the drabness of the E 250 CDI.

The petrol E 250 added brightwork and cream leather trim to contrast with the black/grey hues throughout the cabin. While its maple-style woodgrain was not to my taste, it contributed to a look that was generally richer than the CDI's.

Recognising the importance of first impressions, Benz has engineered the doors of the E-Class to close with just a gentle thrust. E-Class offers generous rear-seat accommodation for adults and the cars' luggage capacity -- thanks due in part to a space saver spare -- was decent too. The powered boot lid was nice, if a little quirky; closing only under its own power.

Seats were typical of the Benz type -- moderately bolstered and a bit flat in the cushion and squab, but providing good support and comfort on longer trips. The steering wheel felt huge, but provided an unobstructed view of the instruments.

Benz's column selector for the transmission was easy to use and freed up room for cupholders, an ashtray, storage under the centre armrest and other facilities in the centre console, including the single-point ('COMAND') controller.

Once the smartphone was paired to the car there was no further need to do anything with either the phone or the audio unit, other than adjust the volume or skip tracks. Headlights automatically switched on or off, and the wipers were the rain-sensing type. Features like these -- allied with ride comfort and serenity inside -- made the E-Class a very relaxing car to drive.

The diesel proved very quiet, although some labouring was felt when the transmission dropped into a higher gear from low revs. With light accelerator pedal pressure applied the engine would frequently run down to 1000rpm without the transmission dropping back a gear. But the diesel Benz was subdued at open-road speeds. The petrol model was even quieter, with driveline noise completely absent and wind and road noise only present in the form of a light rustle.

Not only was the transmission reluctant to shift down at times, at other times it would hold lower gears longer than expected. Clearly, the transmission was adapting to a style of driving based around one brief overtaking manoeuvre, to use one example.

Turbo lag was minimal; the diesel E-Class could be relied on to deliver rapid response to driver input and launch across a busy intersection at a moment's notice. Even so, drivers will likely get in the habit of easing off the accelerator in anticipation of traffic lights changing to green, prompting the engine to restart sooner.

In Eco mode the engine remained off for prolonged periods, saving significant quantities of fuel, but restarting quickly without fuss. Fuel consumption for the week averaged 7.6L/100km, helped by around 120km of freeway driving during that period.

More time commuting cost the petrol-engined E 250 dearly. Fuel consumption finished up at 11.1L/100km. But the petrol model redeemed itself by delivering added driving satisfaction. The peak torque figure of 350Nm looks anaemic against the diesel's 500Nm output, but the petrol model scooted along and revved cleanly to the redline with a crisp exhaust note.

Ride comfort was outstanding and was a foil to the car's safe roadholding, and handling proved very safe, even in the fuel-saving mode. Body control could have been better however, with some rolling and dipping evident in corners. Turn-in was less responsive than an equivalent-spec BMW and steering feel varied on occasion, but switching from Eco to Sport resulted in tidier steering and more feedback.

Distronic Plus with steering assist turns the car with bends in the road, in the event that the driver takes his or her hands off the wheel. Its return to the straight-ahead from exiting the bend was not always elegant. Now and again the system would tug at the wheel in the driver's hands because it couldn't find line markings on one side of the road.

After 10 seconds the system warns the driver (visual initially, followed by an audible alarm) it is handing back control of the car. Resting one hand on the lower section of the steering wheel rim is one ploy to keep the car steering itself beyond that 10-second window, but it's a cheat I don't recommend, needless to say...

The electrically-assisted steering is the lynchpin of Active Park Assist, which requires less preliminary set-up than similar systems offered by other car companies.

One technological advance I recommend highly is Active High Beam Assist Plus. Late at night it cast an excellent spread of light, but never blinded the drivers of on-coming cars.

So which car did I prefer?

While admitting that buyers can specify the E 250 CDI with the same cosmetic features as the petrol E 250, I would probably still choose the latter. There's that added refinement and the power delivery makes it more fun to drive -- if that's your thing -- and none of that detracts from the E 250's comfort.