2002 Fuel line or ventilation ??

[Robdaparamedic]

I finally got around to changing my fuel filter and found the hose just above it leaking. This line has a connector just like one end of fuel filter and goes up toward front of engine, but what is it ?? My service engine light came on last week and I'm guessing this may be the reason ??? Also it only leaks when the car is running...

Rob

[maxwedge]

Sounds like the vapor line or the fuel return line, most likely return if fuel comes out.