Bypass Valve; High Pressure Line - Porsche Cayenne V6 2008 Service Information

Bypass Valve (including pressure relief valve)
Pressure Control Valve
The pressure control valve is integrated into the fuel high pressure
pump. This safety valve opens a connection to the fuel low pressure
system if the fuel pressure in the high pressure system exceeds approx.
2030 psi (140 bar).

High Pressure Line

The high pressure line connects the high pressure pump to the fuel rail.
Fuel, Exhaust & Engine Electrics
1 - Low pressure (approx. 80 psi/5.5 bar from
the fuel tank)
2 - Wobble plate
3 - Fuel high pressure pump
4 - Flow control valve (for fuel high pressure)
5 - High pressure line to fuel rail
Arrow in illustration is wobble plate.
1 - Bypass valve, including pressure relief valve
2 - Volume control valve
Blue - Low pressure inlet from the in-tank fuel
pump
Red - High pressure to the injectors
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