Fuel, Exhaust & Engine Electrics
Page 2.20
Fuel Injectors/High Pressure Injectors
The electromagnetically operated fuel injectors are on the intake side of
the cylinder head. They are activated by the DME control unit in accor-
dance with the firing order. Following activation, they inject fuel directly
into the combustion chamber at a pressure of 580 psi (40 bar) to 1740
psi (120 bar). During this process, a vortex is created even before the
fuel emerges at the valve tip.
The Cayenne S and Cayenne Turbo are equipped with different injectors,
designed specifically to suit the engine’s fuel requirements. The injectors
can be differentiated by their part numbers and a color marking. The
piston recesses in the V8 naturally aspirated engine and the V8 Turbo
are also different so that the injected fuel can be whirled around and
mixed perfectly with the air that is drawn in.
Fuel Injectors -V8 Naturally Aspirated Engine
At a fuel pressure of 580 psi (40 bar) and an injection time of 0.6 ms,
the amount of fuel injected is approx. 5.5 mg/stroke. While at a fuel
pressure of 1740 psi (120 bar) and an injection time of 5.8 ms, the
amount of fuel injected is approx. 67 mg/stroke.
Fuel Injectors -V8 Turbo
At a fuel pressure of 580 psi (40 bar) and an injection time of 0.6 ms,
the amount of fuel injected is approx. 7.8 mg/stroke. While at a fuel
pressure of 1740 psi (120 bar) and an injection time of 6.1 ms, the
amount of fuel injected is approx. 107 mg/stroke.
To Next Page
Loading...
Need help?
General
