Jeep TJ fuel pump 255lph. Do I need a return line?

[ZacharoniousTJ]

Hi all. So I have a supercharged 4.0 L6 and found out last week that my factory fuel pump in the injectors are not supplying enough fuel. After dropping my tank I've noticed that it has been tampered with by the previous owner. There is one large sending line from the factory regulator on top of the fuel tank. Then the two other ports on top the tank which I assume should hook to the fuel return/ vapor return on the tank are vented with short lines. There is a thin vapor line adjacent to the fuel sending line going to the tank but he has it pinched and capped. I was dead set on needing to fix it thinking it was a return line but after looking it appears to not be a return line and only goes to some emissions box or something of that nature. I don't see it connect to the other line anywhere and it is the only other fuel line. Is this ok or correct? Can I assume that it's just in emissions line of some sort and leave it plugged? I'm just wondering how the additional fuel is returned or is it that the factory regulator on the tank somehow has the fuel return line built into it? I have the 255lph oem Walbro pump installed and it seems to run ok but I'm worried it's over pressuring or the pump is dead heading? Any thoughts or knowledge of the factory fuel system would be greatly appreciated.

[ZacharoniousTJ]

This is where the small second line goes in the engine bay. Into the black box on the bottom right. It says evap port. Is that all it is or does it connect as a return line somewhere I'm not seeing. And if not I guess I just don't understand I thought you always need a return line so that the pump is always flowing. Again the only thing I could think is that the regulator on the fuel pump module dumps back into the tank any access fuel. Does anyone know?

[ZacharoniousTJ]

This is where it is capped and pinched off at the tank

[Jim]

Follow lines in reverse... Look at your injectors / fuel rail for a supply and return and follow those two back to the tank.

[ZacharoniousTJ]

Jim previously posted: