Fuel pressure problem

just rebuilt my LT1 and got it running, but i have a fuel pressure problem, with the key on engine off it will pressurize up to 43lbs and instantly drop off to 0. and it is running very rich. i have racetronix 255lph pump, 30# svo injectors. the fuekl pressure regulator seems to be working fine, and there is no fuel in the vacuum line for the fuel pressure regulator. when i turn the key on to pressurize the system it sounds like an injector is squirting badly, but i pulled the rail up and and tried it and none are leaking, i also have checked all the o-rings and oiled them well before i installed the injectors, and have double checked them.....i am stumped????? the computer has been tuned for the injectors....thanks

You have an injector that is sticking open.

thats what i thought but when i pulled the rail and injectors out of the intake ports, i turned the key on and no fuel sprayed out of any of the injectors and i still lost all the fuel pressure right away???