this is in a 01 E-350 and fuel was puddling up in the valley pan and dripping off the right rear onto the ground. Unbelievably aggravating to get to ,even with a small mirror. Finally I pulled the dog box out of the inside,removed the turbo heat shroud,and everything I could get out of the way up front,inclusive of the air filter and housing, and all the intake rubber pipes. I started the engine and looked up through the valley below the turbo from the rear and could see fuel dripping,but not from where. Got to feeling around and believe it is coming from a piece of rubber hose that connects a metal overflow line of some kind, to the lower rear of the fuel filter housing. The other end of this steel tubing ends on the right front side of the engine block. I popped the rubber hose off the housing and it drips fuel from where this hose connected while running,especially when cold. I thought it might have been a priming tube like whats on the old 3208 Cats but I cant find a shut off valve anywhere back there. Can anyone help with an answer ???