Forum Discussion
theoldwizard1
Aug 17, 2018Explorer II
If it does start and run fine, it is probably NOT the fuel pump !
I am guessing that uses a "return" fuel system (as opposed to some others that use a "returnless" fuel system) and it sound like the pressure regulator/drain back check valve is not holding pressure.
Quick check (but not perfect). Turn the key to on and wait 10 seconds. Repeat that 3 times. Now start. If it fires right up, then I was "general" correct, no pressure at the injectors while cranking.
To check the correct way require a fuel pressure gauge. Once connected, do the cycle the key 3 times, but check the pressure after each cycle. After the last cycle and start up, leave the gauge connect and check it about every 5 minutes for a couple of hours. It should maintain the last pressure.
I am guessing that uses a "return" fuel system (as opposed to some others that use a "returnless" fuel system) and it sound like the pressure regulator/drain back check valve is not holding pressure.
Quick check (but not perfect). Turn the key to on and wait 10 seconds. Repeat that 3 times. Now start. If it fires right up, then I was "general" correct, no pressure at the injectors while cranking.
To check the correct way require a fuel pressure gauge. Once connected, do the cycle the key 3 times, but check the pressure after each cycle. After the last cycle and start up, leave the gauge connect and check it about every 5 minutes for a couple of hours. It should maintain the last pressure.
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