In 2004, Mercedes-Benz will introduce the E320 CDI diesel, a more fuel-efficient version of its E-Class sedan. The turbocharged six-cylinder engine features electronic fuel injection, said to be cleaner, quieter, and more powerful than conventional mechanically injected diesels. The common-rail diesel injection (CDI) means the fuel line supplies constant pressure to each of the six solenoid-injector valves. The precise, electronic control of fuel delivery and an oxidation catalyst lets the E320 CDI pass current emission standards in 45 states. The diesel E-Class is said to get over 30 mpg on the highway and can cruise about 700 miles before refueling.