CRD Diesel's

Common Rail Diesel. These engines instead of relying on high pressure fuel from a timed mechanical injection pump utilyze a common high pressure fuel rail and the injectors are usually controlled electronically with help from fuel pressure. Some like the new 3.0 Mercedes in the GC and Sprinter use a Piezo injector, as does the new 08 Super Duty Power Joke which does not need additional help from either a high pressure fuel or oil pump.

I know this is over simplified but you get the idea right?

Maybe an even simpler explanation is each fuel injector is operated by a rocker arm much like the intake and exhaust valve rocker arms and when the rocker pushes on the "plunger" part of the injector very high pressure diesel is injected into the combustion chamber. The rocker is operated either by a push rod and cam or just from an overhead cam.

Terry