Celica Forums News Portal r/Celica 1995 Toyota Celica gt fuel pressure 0 psi but 20 psi when the engine is on [r/Celica]

when I set the car to the start position there is no pressure happening but when I start the engine it will go to only 20 psi but then die right after 30 seconds. I know it can't be a power issue, a fuel pump, or a fuel filter. I did replace the fuel pressure regulator from a junkyard, so I guess it could have been a bad one but was able to make the engine start to sense my old regulator would only crank and wouldn't start. anyone has a suggestion, or could be a fuel regulator issue?