I have a 91LS400 with 213000mi. I am wondering how the fuel systems works. My fuel system seems to be loosing pressure as it sits with the engine off.
Is this normal or should the system stay pressurized after the ignition is off?
The car takes about 4 secs to start for the first time, if it has set overnight. Otherwise, it starts immediately.
If it is supposed to stay pressurized, What could be allowing it to disipate? The fuel pressure regulator or the fuel pump?
If it isn't supposed to stay pressurized, could the fuel pump be getting weak or could the fuel pressure regulator be out of spec?
Other than this there are no visible leaks and the car runs great.
Can anyone help? Class? Anyone?
Thanks,
CL