DDEC Electronic Unit Injectors (EUIs) are a type of fuel injector that is used in Detroit Diesel engines. They are electronically controlled and can adjust the timing and quantity of fuel injected with great precision. This helps to improve fuel economy, reduce emissions, and extend engine life.
The Electronic Unit Injector (EUI), see Figure 2-2, operates on the same basic principle as the
Mechanical Unit Injector (MUI) that has been incorporated in Detroit Diesel engines for over
fifty years.
EUIs are more complex than traditional mechanical injectors, but they offer a number of advantages, including:
- Better fuel atomization: EUIs inject fuel at a higher pressure than mechanical injectors, which results in better fuel atomization. This helps to improve combustion efficiency and reduce emissions.
- More precise fuel injection timing: EUIs can control the timing of fuel injection more precisely than mechanical injectors. This helps to improve engine performance and reduce emissions.
- Reduced maintenance requirements: EUIs are self-cleaning and require less maintenance than mechanical injectors.
The EUI uses a solenoid operated valve to control injection timing and metering. The source for high pressure fuel delivery is the cam/rocker arm system. Fuel injection begins when the solenoid valve is closed. Opening the solenoid valve ends injection. The duration of valve closure determines the quantity of fuel injected.