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The prototype of the common rail engine was designed by Robert Huber of Switzerland in the year 1960. The design was further improved by Dr. Marco Ganser at the Swiss Federal Institute of Technology in Zurich. Dr. Shohei Itoh and Masahiko Miyaki of the Denso Corporation, a Japanese automotive parts manufacturer, then placed the advanced engine technology to practical use in 1990. For the first time, this engine was fitted into a commercial vehicle with an electronic control unit. It was then sold out commercially in the car market.

The advanced common rail engine technology works on a similar principle that controls the conventional engines. The only difference is that the traditional engine were controlled mechanically and the CRDi engine is controlled by an electronic control unit that regulates the amount of fuel injected as well as the pressure utilized and required for both injection and combustion.

The actual use of the engine control unit (ECU) with regards to the CRDi engine was prototyped by Magneti Marelli, Centro Ricerche Fiat, and Elasis in 1990. Thereafter, the Fiat group did the actual research and development on the possibilities and advantages of placing this effective engine into cars. The design of the final engine was adopted and mass produced by the German company Robert Bosch GmbH. The company surprisingly received a good response for the engine system. The first passenger cars fitted with the CRDi engine was the Alfa Romeo 156 in 1997. Later in the same year, Mercedes-Benz adopted this high pressure engine technology for Mercedes-Benz C 220.

The CRDi engine works in association with the solenoid valve. This is an electromechanical valve that controls the flow of liquid or gas by running or stopping the flow of electric current. This valve electronically controls the time and quantity of fuel injection along with the amount of high pressure generated by the engine. This further improves fuel atomization.

The engine works to lower the level of noise and vibration. In order to lower the engine noise, the control unit injects a small amount of diesel just before the actual injection or pilot injection, reducing explosiveness and vibration. It also optimizes timing and quantity of fuel injection for different quality of engine fuels.

In common rail engine system, the high pressure fuel pump stores a reservoir of fuel at a pressure of at about 29,000 psi in a common rail. This common rail is actually a tube which branches off to computer-controlled fuel injector valves that comprise a precision-machined nozzle and a plunger driven by a solenoid valve. The fuel reservoir then pumps out the fuel to multiple injectors that are electronically controlled by the engine control unit. Under the control of an on-board computer, the engine regulates the fuel quantity and pressure. It also controls the precise moment when the actual process of fuel injection occurs and also increased the pressure at which fuel is injected. This in turn results in better fuel atomization and combustion, eventually leading to lower exhaust emissions, lower fuel consumption, and increased fuel efficiency.