Right now, I can't think of a reason why anyone wouldn’t love this motorcar. It’s a handsome, balanced looking car. It is really pretty quick for a generous-sized German sedan, at 6.8 seconds to 60 mph (quicker than the gasoline E 320). It has bags of torque. It handles beautifully, with a nice combination of steering, suspension, and road feel. It has a commodious, attractive, and comfortable interior. It has a huge trunk. And it gets great fuel mileage, even if you flog it hard (more on this below).
But it’s a diesel, you say, a diesel, how can anyone love a diesel? Isn’t that a contradiction in terms? Aren’t diesels practical, economical, stolid, unemotional, ahem, unpleasant? Not hardly, not any more.
Let’s do diesel first. And by the way, diesel is diesel because of Rudolph Diesel (1858–1913) who thought up the compression-ignition system.
This new model year 2005 E320 CDI (for common-rail direct injection) is the first such entry since Mercedes-Benz quit diesels here in 1999. In that interim period of time, it was a quiet but fertile one for key diesel technology, including the development of common-rail diesels. In common-rail direct diesel injection, the common “rail,” essentially a pipe that looks kind of like a simplified flute, is under constant pumped pressure, at upwards of 20,000 psi, and very precise injectors fed by it squirt fuel directly into the combustion chambers, where there are no spark plugs necessary, owing to the exceptional compression of air and fuel in diesels. The holy grail in high-pressure common-rail diesel direct injection is rapidity, precision, and controllability of injection “events,” so combustion chamber phenomena can be very precisely modulated and controlled. CDI reduces combustion noise as well as creating smooth and complete combustion, with lowered NOX emissions.
Given the move forward with CDI and the coming of superior, low-sulfur fuels to the U.S. later in the decade, diesels may be poised for rapid growth here. Once both are in place, there will no longer be any reason not to drive a diesel — no more smoke or smell, no more rattling or crunching noises associated with diesel engines. The only thing that would signal “diesel” — the only thing — is more low-end torque than you are used to. That, and maybe the fact that you can go from L.A. to San Francisco and back again on a single tank of fuel.