Fuel pump prime
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From: SoCal 909
Fuel pump prime
How long do the fuel pumps prime on these trucks? I remember hearing something about 1 second, then turns off until you start it. is it different for different years? asking for my '92.
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From: SoCal 909
Ok, that's what I thought. My truck is still doing that longer crank when warm after driving even after new fuel filter. Im gonna do a pressure check on it when I get a tester. what should KOEO pressure be?
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From: SoCal 909
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From: SoCal 909
Just pulled the pressure
Pump primes rail to 35
Engine running is about 32
Jumps up to 41 or so with vacuum line off of FPR
Then with engine off it drops to zero within a minute.
That's the same readings on both tanks
I'm really stumped guys. Please help. Thanks. Other then the longer crank on warm engine no complaints on performance. Thanks
Blaine.
Pump primes rail to 35
Engine running is about 32
Jumps up to 41 or so with vacuum line off of FPR
Then with engine off it drops to zero within a minute.
That's the same readings on both tanks
I'm really stumped guys. Please help. Thanks. Other then the longer crank on warm engine no complaints on performance. Thanks
Blaine.
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From: Kentucky
I would be concerned of the quick pressure drop off. Could be a leaking injector or bad Fuel Pressure Regulator.
Similar thread here: https://www.ford-trucks.com/forums/1...ank-times.html
Similar thread here: https://www.ford-trucks.com/forums/1...ank-times.html
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From: Easton,Ks
41 is a little high as the FPR spring is set for sightly below 40psi. It also sounds like you are loosing fuel pressure as the engine is turned off. This may be a bad FPR or check valves in the fuel pumps or a leaking fuel injectors. A cold engine needs a richer fuel mix then a warm engine so it could be the leaking fuel injectors.
But it may turn out to be just a bad ECT or IAT sensor.
But it may turn out to be just a bad ECT or IAT sensor.
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From: SoCal 909
Truck runs fine. Just when warm have to prime twice or do the longer crank. And it's on both tanks. Same exact pressure everything. No raw fuel smell from pipe or under hood. Hoping it's something easy like the FPR
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From: Easton,Ks
If you turn the key on and then off three or four times before you try to start it and it starts right up then it is not the fuel injectors.
You either have an open check valve in a tank FDM or a bad FPR.
You either have an open check valve in a tank FDM or a bad FPR.