1997 Chevy Silverado Fuel Pump Pressure Proublem

My truck only runs when I spray starter fuild , but when I step on gas pedal it stall . I replace the fuel pump ,I replace the TPS sensor and replace cam crank senor also. It is a vortech engine 5.7 liter. When turn ignition to on position without starting it, fuel read 52 psi . Can you please help me .

PS I also replac the fuel filter