Excellent question. I don't know the answer but it reminded me of a question I had for the group. If Juan were to want to run a return line to the tank, for fuel injection or something, does one of the lines return to the tank or do they go to the charcoal cannister? I can see several lines running to and from the front and back of the car but I don't know if any go into the top of the tank. I guess I could look in my service manual but anyone who knows me can attest that I'm far too lazy for that.
Tim
ps This is for US spec cars.