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Is Fuel Pump Failed

Rickb1b

Sr. Member
Joined
Feb 29, 2012
Messages
447
So before I drop my tank and replace the fuel pump I’d like to hear from the experts. I have an EFI tank with in tank pump I got from bronco hut. So today the truck starts running really bad and won’t stay running. I do all the diagnosing, what I find is the fuel pump gage is reading around 10 psi. Should be around 60 psi. I disconnect the fuel line and the pump is pumping quite a bit of fuel. So I’m questioning whether it’s actually failed. In an attempt to make sure, i disconnect the fuel line and put the gage directly after the fuel line with no return line. This gives me a direct pressure reading of the pump from the gage. It initially reads about 10 psi then drops to zero. But the pump is still running, just no pressure.

Have any of you ran into this. The pump pumps fuel, just not at the required pressure for my EFI system.
 
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Rickb1b

Sr. Member
Joined
Feb 29, 2012
Messages
447
Pretty sure it’s full. I just filled it. Although, this did cross my mind. Could someone have stole the gas out of it, don’t know. But it did pump fuel when I disconnected the line. So there is definitely some fuel in there.

Don’t know the brand of pump, it’s whatever Bronco Hut put in their tanks.
 

SP73

Full Member
Joined
Jun 25, 2017
Messages
165
I had that exact problem with my Bronco Hut efi tank. I replaced the pump, but found the filter sock around the pickup was clogged. I’ve had zero problems since replacing the pump and sock though.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
37,074
Sounds like you already dead headed the pump to check for pressure. But if you had not done that yet, when checking a low pressure issue just pinch the return line. If the pressure spikes, the regulator has failed open. If it stays low, pump issue.

Clogged filters won't make a change in pressure if there is not flow. The will hurt pressure when there is flow. So your dead head test pretty much says the pump is dead.
 

brewchief

Sr. Member
Joined
Feb 11, 2007
Messages
877
Sometimes a short piece of hose is used to connect the fuel pump to the exit on the tank inside the tank, it's possible that this hose has failed and is leaking internally back into the tank. That hose has to be a type designed to be submerged in fuel, if not it will fail.

Sent from my SM-G965U using Tapatalk
 
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Rickb1b

Sr. Member
Joined
Feb 29, 2012
Messages
447
Thanks guys, yep the pump was bad. Put a new one in today and all is good.
 
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