Need Help With Fuel Delivery......
I have a 05 TJ with a 5.3L/4L60E powertrain.
Upon logging some files with efi live, I have noticed that my fuel delivery is not adequate for the engine. I am currently running the stock TJ in tank fuel pump system. The stock system runs 60 psi (internally regulated), but the flow is not enough.
My question is:
I bought a walbro 255 lph in line fuel pump to fix this problem. I will be running a corvette filter/regulator to send un-needed fuel back to the tank.
Can I run the stock pump still to send pressure to the walbro pump, then the walbro pump increase the pressure to the motor (kinda like a lift pump and primary pump diesel system), or will that not work?
I know I have to drill a hole in the top of the tank for a return line (since the stock system is internally regulated) and i can do the same for a supply line if I cant use the stock pump, but I dont know if the walbro pump will last very long sucking fuel out of the tank. I always heard inline pumps hate the suction part and they dont last long due because of it.
Any help will be much appreciated...
What mods are done, that would require more volume?
What's the flow rating/psi on the current pump?
Is the current system a return style setup?
How is EFI indicating U R short on volume?
Adding an external pump, and supplying it w/ one that's of lower volume won't cure your problem..
Adding the Vette reg and leaving the intank reg won't work, either.
Y not replace the internal pump w/ another that has the capacity for sufficient flow??
The log (done with efi live) shows that fuel delivery is more than 20% low and the motor is running lean.
There is no higher volume drop in replacement pump for the 05-06 Jeep module, only the 97-04 which is way different.
Do I just need to unhook the pump I have now and drill a couple of holes in the tank to put in a supply tube and return tube, and run them to the pump and regulator?
What would you guys do?


