[amac209]

pressure must be at least 60psi or the injectors won't work. will it start if you cycle the key on and off about 4 times, waiting for the pump to stop each time?? i assume you already have a pressure gage. most likely is the check valves in the pump are shot and losing pressure after it's shut off. try pinching the return line with some visegrips while the gage is attached with the engine off, does it still loose pressure?? if not the regulators your problem. follow the fuel lines to the regulator there should be a vacuum line attached pull it off and look for any fuel leaking into it. just so you know chevy fuel pumps die all the time. the easiest way to replact the pump is to remove the bed assuming you don't have a canopy or big tool box back there. if you change the pump always replace the fuel filter. good luck