Guardian Generator

I have a 05 Gulf Stream with a Guardian Generator.When I shut it off the fuel pump keeps pumping, I have to pull the fuse to stop it. I dont know if its a bad fuel pump or control board or something else. Anybody had the same issue? If so what did you have to replace? Ive been having trouble with it shutting down after a while of use but the fuel pump just started doing this. I figured it was vapor locking before but maybe its all from the same problem.