What is it?
Just a few years ago, the notion of placing a four-cylinder engine in a car like the S-class seemed… well, implausible. But with fuel prices having shot up quite dramatically in the meantime and an increasing number of countries looking towards road tax laws tied to CO2 emissions like those in force here in the UK, that’s exactly what Mercedes-Benz has been prompted to do. The result? The most economical S-class ever placed into production: the S 250 CDI.
What’s it like?
The new Benz gets all the latest fuel-saving technology, including stop-start, and its turbocharged 2.1-litre diesel engine manages 201bhp and a sturdy 368lb ft of torque; it gives away 53bhp and 89lb ft to the 3.0-litre V6 diesel-powered S 350 CDI.
The relatively small engine does a commendable job of hauling the S 250 CDI’s considerable 1895kg. Granted, it’s quite leisurely off the line, making it somewhat frustrating around town. But with clever gearing taking full advantage of its strong low end torque, it delivers convincing in-gear performance once you’re wound on some speed on the open road.
Besides an uncharacteristic four-cylinder thrum under hard acceleration, the new engine is also very quiet for a diesel on a constant throttle, providing the sort of relaxed cruising the S-class is renowned for.