Principle of operation
Common rail diesel
The 2.7L fuel injection system is a common-rail design, running at the high pressures (up to 1,650 bar or 23,931 lb/in 2 ) typical of such systems.
The fuel is drawn from the fuel tank by an electric lift pump and delivered to the transfer pump side of a high pressure fuel pump (HPFP) driven by the engine. For additional information on the HPFP, Refer to Fuel Charging and Controls article.
The fuel volume control valve (FVCV) regulates the amount of fuel supplied to the high pressure side of the HPFP, while the fuel pressure control valve (FPCV) regulates the pressure. Both valves are controlled by the engine control module (ECM) using inputs from the engine management sensors covered.
The high pressure fuel is delivered to the fuel rail where it is stored, ready for use by the injectors.
The fuel injectors are Piezo type, and are controlled by the ECM using inputs from the engine management sensors covered.
The injectors operate in stages, giving a pilot injection before the main injection to reduce detonation noise and help improve the efficiency of the engine. For additional information on the fuel injectors, Refer to Fuel Charging and Controls article.
For additional information on the description and operation of the system, See Electronic Engine Controls .