Fuel Pressure Question
Fuel Pressure Question When you turn the ignition switch on (not the car but just the switch) is your fuel pressure suppose to go to rise? Mine gauge reads 0 until the car is turned on however i do hear the gas rush through the lines when the ignition switch is turned.
From what I always thought when you first turn it on it primes the system, then when you start it, it pressurizes everything. Mine doesn't have any pressure till the Car is running aswell..I have a Walbro 255 Pump.
Turning the key to the on position without starting it, primes the pump. Your fuel pressure gauge should read 43.5 psi (40-47 is ok) at the schrader valve. If you don't, you might have a bad fuel pressure regulator or a bad check ball in your fuel pump.
Yea, nothing comes up till it's actually running. I've never had any issues with pressure and no leaks, so I know it's good. That first wine is just the Pump priming. There is Fuel in the Lines, so once it kicks up it pressurizes everything.
I would check to see if your pressure immediately drops to zero after you shut it off. If it does, than you might have a bad check ball or something in your fuel pump. When my pump primes (as well as numerous Fbody's I have tested) once you prime the pump, the fuel pressure shoots up to normal, and holds until it is started. You have an issue, but it's probably something that can be ignored.
I would check to see if your pressure immediately drops to zero after you shut it off. If it does, than you might have a bad check ball or something in your fuel pump. When my pump primes (as well as numerous Fbody's I have tested) once you prime the pump, the fuel pressure shoots up to normal, and holds until it is started. You have an issue, but it's probably something that can be ignored.
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I can't say for 100% certainty, but a properly configured (and operating) fuel system should have fuel in the lines and rail after you shut the car off and when you go get back in it. It should also turn the pump on during KEOE (Key On Engine Off) to prime the system, since it's understandable for some fuel to drain back. You also won't get fuel pressure just by putting the gauge on the shrader valve with the engine off. Again, this is just an educated assumption 
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