Low fuel pressure

Tiny
93FORDMAN
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  • FORD EXPEDITION
I have a 1998 Ford Expedition 5.4, it has 92,600 miles. I have replaced the fuel pump & the fuel filter, I have checked the fuel relay in the distribution box & the fuse. I have disconnected the fuel filter & with the ignation on there is almost no gas coming out of the line. Any suggestions?
Sunday, January 14th, 2007 AT 8:06 AM

12 Replies

Tiny
SERVICE WRITER
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Thanks for the donation! :D

What brand of pump did you use?

Was the pump replaced to fix an issue or was this done at an earlier date?

Is this a 4x4?

Does it have air suspension?
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Sunday, January 14th, 2007 AT 8:11 AM
Tiny
93FORDMAN
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Brand is a Master
The pump was replaced two days ago vehicle would not start
4X4 yes
air suspension no
:
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Sunday, January 14th, 2007 AT 8:46 AM
Tiny
SERVICE WRITER
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Charlie,
My experience is anything electical from Autozone is junk. Based on the TSB, I'd put in the dealer pump. I am real leary of a lot of aftermarket pumps. We have had bad luck with a lot of brands. Chysler ones I always go dealer. Gm -ac delco, Ford I recommend dealer, and don't give a labor warranty if aftermarket is chosen.
I'd drop the tank if you have to and blow air through the line to make sure it isn't plugged and check for proper power flow to the connector. If good use the ford revised pump according to the tsb spec sheet.
PAul
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Sunday, January 14th, 2007 AT 10:01 AM
Tiny
93FORDMAN
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I have found that the volts going to the fuel pump shut-off switch is 12.5 and coming out is 7, does any one have any suggestions : Thanks Charlie
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Wednesday, January 17th, 2007 AT 6:44 AM
Tiny
CARUNDELL
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Hey Charlie,
Looks like you've got the problem nailed! Your referring to the inertia switch right? A quick to to verify would be to disconn the switch and jumper the connection and. Viola. Good fuel pressure should return

Chris
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Wednesday, January 17th, 2007 AT 2:26 PM
Tiny
93FORDMAN
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Chris I thought so to, I put a jumper and got 12.5 volts so I thinking that it was going to work, put the unit in the tank and hooked everything back up and with the jumper in place it did nothing : this has been a pain. I was talking to Paul and he said you are good at this kind of problems. Do you have any other ideas? Thanks Charlie

My email address is rocker1950@comcast. Net if you don't mine sending me your phone number I will call you.
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Wednesday, January 17th, 2007 AT 6:14 PM
Tiny
CARUNDELL
  • MECHANIC
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Wow, its bein' real pain. Time for some more testing! Have you done voltage tests further down the line? I would go right to the fuel pump connector and test there. Don't forget test test for a good ground also!
Let me know how that goes! Will email ya my biz # if all else fails!

Chris
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Wednesday, January 17th, 2007 AT 6:58 PM
Tiny
93FORDMAN
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Yes, with the unit out of the tank and the jumper hooked up I got 12.5 volts at the plug that goes the the fuel pump, when I put it all together the pump did not run
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Wednesday, January 17th, 2007 AT 7:29 PM
Tiny
CARUNDELL
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Ok, and you verified a good ground for the fuel pump assy?

Chris
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Wednesday, January 17th, 2007 AT 7:32 PM
Tiny
93FORDMAN
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Do you mean when it goes in the tank and locks down?
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Wednesday, January 17th, 2007 AT 7:45 PM
Tiny
CARUNDELL
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Charlie,
Ummmmm yup, we need to verify that there is not only got voltage to the f/p but also a good ground! Do you know how to test for that? Am emailing you my biz #

Chris
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Thursday, January 18th, 2007 AT 4:33 AM
Tiny
93FORDMAN
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The problem was a bad key, the dealer cut a new key and programmed it and it is running fine. Thanks to Paul and Chris for your suggestions. :D
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Wednesday, January 24th, 2007 AT 7:39 PM

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