When installing the Walbro I noticed another what looked to be another fuel return line that I have never seen before. There's one at the CP3, fuel rail, and then there looks to be one that is super close to the firewall. It is farther back than the last injector line and looks to run behind the valve cover down to the side of the fuel filter housing. Where is it returning fuel from? It's puzzled me for awhile now, someone please shed some light on this so I can get a decent nights sleep.

 

there is a rail in the head that goes to the back of the head , if one of the fuel connectors to the injectors every spring a leak that is the return that you are seeing.