Sound like the fuel pumps not doing it job if the fuel pressure drops off quick. Might also be the regulator but most likely the fuel pump is not pumping enough. They only time the fuel pressure should drop off it when you bring the rpm up and it shouldn't drop off that much maybe 5 psi at most any thing below that i would change the fuel pump.
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Sound like the fuel pumps not doing it job if the fuel pressure drops off quick. Might also be the regulator but most likely the fuel pump is not pumping enough. They only time the fuel pressure should drop off it when you bring the rpm up and it shouldn't drop off that much maybe 5 psi at most any thing below that i would change the fuel pump.