1999 E150 when filling up tank gas comes out from top of tank. Does not leak any other time just when filling up. Could this be making the van run rough also. Got a code reading of P0442 could this leak be causing the code and engine run rough

 

This code involves the evaporative emission system. When adding fuel to the tank, a purge valve in the lines is supposed to be closed which appears to be working. There is ,however, a vent valve that is supposed to be open to allow tank vapors to go into a charcoal canister to be stored until conditions are met and the vapors are purged into the engine and burned. It does sound like the vent valve is not opening to allow the pressure on filling to exit thru the canister to the atmosphere. Many times the vent filter just gets so dirty it blocks the exit. That should be checked first. The vent valve should be located near the charcoal canister assy. Either valve malfunctioning could produce a rough idle condition.

 

I have a '93 E-250 that leaked gas when filling. Turned out to be a cracked fill hose. It split, lengthwise, on the topside and would not be visible unless you used a mirror. Found a replacement at a Ford dealer and while changing that hose replace the vent line that runs from the tank to the tank cap port.