Yes I have a 1/4 line? coming from the front of the car into the top of the tank. I believe it did go into the charcoal cannister that I currently do not have. The line is just open at about where the fuel line ends, below the passenger side manifold. No cali. emmisions, just the one return (vent) line. Yes the vent line. If there is blockage there, that is probaly going to cause problems, right?