Fuel Metering System Description
FUEL METERINGThe Engine Control Module (ECM) is in complete control of this fuel delivery system during normal driving conditions.
The intake manifold function, like that of a diesel, is used only to let air into the engine. The fuel is injected by separate injectors that are mounted to the cylinder head.
With receipt of the signals sent from the MAF sensor, Intake Air Temperature sensor and others, the ECM determines an appropriate fuel injection pulse width feeding such information to the fuel injector valves to affect an appropriate air/fuel ratio.
The Direct Fuel Injection system utilizes an injection system where the injectors turn on at every crankshaft revolution. The ECM controls the injector on time so that the correct amount of fuel is metered depending on driving conditions.
One interchangeable "O" rings and another interchangeable tip seal are used on the injector that must be replaced when the injectors are removed.
The fuel rail is attached to the cylinder head and supplies fuel to all the injectors.
Fuel is recirculated through the rail continually while the engine is running. This removes air and vapors from the fuel as well as keeping the fuel cool during hot weather operation.
The fuel pressure control valve that is mounted on the high pressure fuel pump maintains a pressure differential across the injectors under all operating conditions.