2007 fxd dyna superglide started running rough after the engine light turned on. makes a loud hissing noise near the fuel tank

The hissing........do this once. turn the bike to the "on" position. Dont start the bike, just turn ity so you can hear the fuel pump engage. After the pump stops, listen really close to the inside of the tank......do you hear anything, like some gas still sprinkling out inside the tank? hopefully, you are at about a half tank or less. You wont hear it with a full tank. need to know where this hissing is from, under or in the tank. you arent going crazy.........yet. :o) I'll keep an eye out for your response.