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ton and combustion chambers along with the design of the intake ports and valve train. In order to inject diesel fuel at high pressures, you need a very unique pump known as a highpressure fuel pump. The pump is usually engine-mounted and driven by the engine gear train. A regulator controls the amount of pressure that the pump makes. The regulator, also known as the fuel-metering valve, regulates the amount of fuel that the high-pressure fuel pump will intake. Even though the engine drives the high-pressure pump, the pump will produce the necessary high pressures regardless of the engine speed. After the pump has been pressurized, the fuel is stored in the fuel rails. The fuel rails are accumulators for the high-pressure fuel to be delivered to the injectors through lines that branch off of them. The fuel rails also dampen vibrations from the high-pressure fuel pump and
After the pump has been pressurized, the fuel is stored in the fuel rails, which are accumulators for the high-pressure fuel to be delivered to the injectors through lines that branch off of them.
injection cycles from the injectors. Inside the fuel rails is a fuel rail pressure sensor that reads the pressure in the fuel rail for the PCM (powertrain control module). The PCM uses the
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40 October 2013 | UnderhoodService.com