Fuel Pressure Normal for 5.3 Flex fuel E38

[bigdaddy9185]

I have a flex fuel 5.3 E38 gen 4
My fuel pressure is running about 42-44 Is this normal for this engine or am I going to need to replace the pump , been told that it is normal and also that It should be between 58-60 psi . so my question is which is it supposed to be so that I can determine if I am going to need a fuel pump replacement to finish my tune

[bigdaddy9185]

Well I found out that normal pressure for this truck is 43.5 to 48 psi and that you can change the pressures in the fuel system section. BUT i would not recomend a change higher that 48 psi , reason is the injectors can not handle the pressure and will leak fuel into the engine while not running and fill crankcase with fuel slowly . brought pressure back to 45 psi low and 48 high and runns great and no more fuel in the oil and fuelmileage is better than stock and better power without the downside of bad mileage and fuel in the oil.