How Does a Cummins Common Rail Injector Actually Work? Unlike older systems, the Common Rail system separates the generation of pressure from the injection of fuel. Here’s a simplified breakdown: High-Pressure Pump: A single, high-pressure pump (the "common rail") continuously pressurizes fuel to extremely high levels—often upwards of 30,000 PSI or more. Fuel Rail: This high-pressure fuel is stored and distributed in a tube called the fuel rail, which runs along the engine's cylinder head. The Injector's Job: Each injector is connected to this rail. When the Engine Control Module (ECM) sends a precise electrical signal, it activates a solenoid or piezoelectric actuator inside the injector. This opens a tiny valve for a nanosecond, allowing the highly pressurized fuel to atomize into an incredibly fine mist as it sprays into the combustion chamber. This precise control over the timing, duration, and pressure of each spray is what makes Common Rail engines so powerful, efficient, and clean. https://www.cq-longshine.com/cummins-common-rail-injector-and-pump/cummins-common-rail-fuel-injector-0445120361