Fuel Injector: Description and Operation

V6 DFI Engine

The fuel high pressure system in the V6 DFI engine is made up of the following parts/components.







Fuel Injectors/High Pressure Injectors







The electromagnetically operated fuel injectors are located in the cylinder head. They are activated by the Motronic control unit in accordance with the firing order. Following activation, they inject fuel directly into the combustion chamber at a pressure of 580 psi (40 bar) to 1740 (120 bar). The injectors for both cylinder banks are on the intake side of the cylinder head. This arrangement allows the injectors for cylinders 1, 3 and 5 to run through the inlet port on the cylinder head. The injectors for cylinder bank 1 are therefore longer than the injectors for cylinder bank 2.

Since the injectors are inserted from the same side for both cylinder banks, the piston recesses of cylinder bank 1 and 2 must be molded differently so that the injected fuel is whirled around and mixed perfectly with the air that is drawn in. This is necessary because the fuel injectors and intake valves on both cylinder banks are arranged in different angles.

In addition to the amount of fuel injected and the injection time, the shape and alignment of the fuel jet is also important here. A defective injector is detected by the misfire detection system and is not activated again.