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YOUR RESEARCHFuel supply and return which is which? - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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Install after the rail
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Right, but typically these regulators are installed after the rail to ensure they are maintaining rail pressure (unless I’m wrong).
Fuel supply and return which is which? - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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Leading evidence: 'Install after the rail' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Disconnect fitting' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion
Does anyone know whether there is an o-ring in the disconnect fitting that can be replaced?
Fuel supply and return which is which? - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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This is a bit of an embarrassing question that I could have answered myself if I still had the original engine in the car but does anyone know what is the fuel supply and what is the fuel return line? I shamelessly stole this photo off another thread so if its your photo thanks.
I would think but don't know that the larger line ( blue arrow ) is the supply and the smaller is the return . Hopefully someone smarter than me
will chime in .
On the early cars, it was a vacuum operated diaphragm device on the fuel rail, as in the diagram.
The early fuel system included a return fuel line and had a fuel rail mounted fuel pressure regulator. For 2002, there is no return fuel line and the fuel pressure regulator is mounted in the fuel tank.
OK, seems after checking the early service manual, I have the lines reversed: The fuel pressure regulator in on the
return
line. Sorry bout that......��
Right, but typically these regulators are installed after the rail to ensure they are maintaining rail pressure (unless I’m wrong). Do I have this backwards?
I think the question was also wrong
So, just to clarify, the right one that runs from the regulator is the return line. The left one (red) is a vent line. The feed line is not pictured, it is on the other side of the rail and is coming up from the fuel filter on the right side of the car. At least on mine, which is a 99 Base.
My fitting at the blue arrow is slightly wet/weeping. Does anyone know whether there is an o-ring in the disconnect fitting that can be replaced? Other options of repair? And my vote is that it (blue arrow) is the return line (98 base)
Mine was leaking too, but not at the connector, but at the fuel rail, and it was leaking down on the back side of the line. If it leaks at the connector, it`s also possible that the line itself is scratched where the fitting slides onto.
This is a source reference. Confirm exact model applicability in the original material.
