I think you're quoting the max pressure, like "dead head". When working properly the system will never need more than 55psi, unless you add boost.Well now I’m seeing like 80-90 psi for the EP381. Don’t know where I got those other numbers from
Something in your setup is leaking. The pump check valve holds pressure at one end and the regulator holds pressure at the other, so either one can be to blame. Assuming you've verified no leaks at any fittings, fuel rails, etc., it's also possible to have a leak inside the fuel tank. There is typically a hose from the pump to the sender outlet and a split hose or bad clamp can let fuel shoot around in there. Crimping off supply or return line is a good place to start.
Do you have a scan tool? If you're running with low fuel pressure and the other sensors are working right, the LTFT number should be going up.


