Mercedes-Benz, the company that invented the diesel car, is debuting a new diesel-powered car for the U.S. market. The company will market the E320 CDI as a fuel-efficient diesel version of its successful E-Class sedan. The E320 CDI is scheduled to make its market introduction in the U.S. this spring as a 2005 model.
The new high-torque diesel engine is quiet, fuel-efficient and has lower exhaust emissions than previous diesels, Mercedes Benz said. The turbo-charged six-cylinder powerplant will feature full electronic fuel injection, considered technically impossible on a diesel until only a few years ago. CDI stands for “common-rail direct injection” — a term denoting the fuel line loop supplying constant, very high fuel pressure (up to 23,000 psi) to each of the six solenoid injector valves. Relying purely on the heat of highly compressed intake air to ignite the fuel, diesel engines operate without spark plugs or other ignition parts.
The leap to electronic fuel injection means that the E320 CDI engine can be cleaner, quieter and more powerful than conventional mechanically-injected diesel engines, Mercedes Benz said. Diesel powerplants inherently produce 20 to 30 percent lower carbon dioxide emissions and significantly lower carbon monoxide than gasoline engines, but historically, diesels have produced more oxides of nitrogen and soot or particulates.
However, with precise electronic control of fuel delivery, hand-in-hand with an oxidation catalyst, the E320 CDI can pass current 45-state emissions standards. When low-sulphur diesel fuel becomes available in the U.S. in late 2006, Mercedes-Benz engineers are optimistic that the CDI diesel can meet emissions standards in all 50 states.
Mercedes-Benz debuted the world’s first diesel passenger car — the 260D — in 1936. On a global basis, diesel engines power about 40 percent of Mercedes cars around the world. In the 1980s, more than 75 percent of the Mercedes-Benz cars sold in the U.S. market were diesel-powered. But in the 1990s, diesel cars became a smaller and smaller part of the company’s product mix. Mercedes-Benz last offered a diesel car — the E300 Turbodiesel — in 1999.
The E320 CDI gets 27/37 miles per gallon for city and highway driving, respectively, compared to the E320 gasoline engine fuel economy of 19/27, the company said. The CDI can reach 0-60 mph in 6.8 seconds (preliminary data), 0.3 of a second faster than the gasoline engine, Mercedes Benz said.
The latest generation of electronically injected CDI engines is likely to change consumer perceptions about diesel engines. Electronic control of diesel fuel injection even makes it possible to soften the power pulses and help make the diesel nearly as quiet as a gasoline engine, even during idle conditions, the company said. CDI diesel technology is expected to help expand the company’s product portfolio in the U.S. market. In addition, Mercedes-Benz’s role in alternative powertrain development means that its modern diesel engine is likely to play a key role in the company’s future products that could include hybrids, fuel cells and advanced piston engines.