where does the vent coming off the sending unit go? i just pluged it off for now because i didnt remember one being there before. doesnt the tank just vent out the gas cap.
Since vent lines normally came out of a high point on the tank or were built into the filler tube I suspect that you have a sending unit with a fuel return installed.
There should be a vent tube right behind your filler tube. 1/4 metal line with rubber pieces, on the top end near the cap it fits over a small nipple. The vent line and filler tube both fit thru the same floor grommet under the wood floor.