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Resolved Fuel pump not turning on

  • Thread starter Thread starter 3054tony
  • Start date Start date Nov 9, 2023

3054tony

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Nov 9, 2023
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Nov 9, 2023
#1
  • Nov 9, 2023
  • #1
Hello, sorry long post but my 93 5.0 has been sitting for 13 years but getting ready to move so I wanted to be able to drive the car onto the trailer and into the new garage. I drained all the old gas out by siphoning it from the tank then jumped the relay to get the rest out. Added fresh gas but had low fuel pressure. Installed new regulator and had 40psi and car ran but heard an air leaking under the upper manifold. Vacuum hose was dry rotted so I ordered new hoses, while waiting for the hoses to come in I flushed the coolant, new thermostat, spark plugs, l replaced the gaskets for the egr, throttle body and spacer. New Vacuum hose came today so I put that on, went to start the car but now the fuel pump won't come on. I tried to jump it at the relay again but didn't work. Been trying to look at wiring diagrams to see if it's possibly a ground or the fuse link. Any suggestions on where to start? Didn't want to drop the tank and do the pump unless everything else was ruled out first.

This was my first car I ever bought. learned how to drive a manual , how to work on it but after sitting so long I'm so rusty I don't know where to start
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Nov 9, 2023
#2
  • Nov 9, 2023
  • #2
Got a test light? Volt meter?
Code reader?

Cranks OK, but No Start Checklist for Fuel Injected Mustangs

Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995 A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work...
www.stangnet.com
jump down to #3 and look for CLUE, that paragraph will show you how to jump the fuel pump (you may know this or remember) #4 will tell you more about dealing with the fuel pump.
Let us know the results or any more help/questions in this thread.
 

3054tony

Member
Nov 9, 2023
49
17
18
Us
Nov 10, 2023
#3
  • Nov 10, 2023
  • #3
General karthief said:
Got a test light? Volt meter?
Code reader?

Cranks OK, but No Start Checklist for Fuel Injected Mustangs

Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995 A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work...
www.stangnet.com
jump down to #3 and look for CLUE, that paragraph will show you how to jump the fuel pump (you may know this or remember) #4 will tell you more about dealing with the fuel pump.
Let us know the results or any more help/questions in this thread.
Click to expand...
yessir I do have a test light, volt meter and code reader. Just pulled a 95 code, fuel pump secondary circuit fault. I am getting power to the relay. Will head back out on my next break and see.if there is power to the pump.
 
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3054tony

Member
Nov 9, 2023
49
17
18
Us
Nov 10, 2023
#4
  • Nov 10, 2023
  • #4
General karthief said:
Got a test light? Volt meter?
Code reader?

Cranks OK, but No Start Checklist for Fuel Injected Mustangs

Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995 A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work...
www.stangnet.com
jump down to #3 and look for CLUE, that paragraph will show you how to jump the fuel pump (you may know this or remember) #4 will tell you more about dealing with the fuel pump.
Let us know the results or any more help/questions in this thread.
Click to expand...
Power is getting to the pump but not kicking on so ordered a new pump. Guess I drop the tank tonight and wait for it to come in tomorrow and hope for the best
 
Reactions: General karthief

3054tony

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Nov 9, 2023
49
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Nov 10, 2023
#5
  • Nov 10, 2023
  • #5
I think im just going to order a whole new tank
 
Reactions: General karthief

2000xp8

SN Certified Technician
Aug 8, 2003
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Nov 10, 2023
#6
  • Nov 10, 2023
  • #6
Not sure what comes with a new tank, but make sure you have new seals and sending unit. I'd also consider the tank to filter hose.
And without a doubt a tank strap stud kit. That's a real mess and i would not be going back in there again.
 
Last edited: Nov 10, 2023
Reactions: 3054tony and General karthief

AeroCoupe

lube between the nut and the face. I know my lubes
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Nov 12, 2023
#7
  • Nov 12, 2023
  • #7
If the wiring at the pump hanger and at the sending unit is fubar you can get a new harness.

https://lmr.com/item/LRS-9002-WH/1986-1993-mustang-fuel-tank-harness-50-resto-5-0-2-3
 
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3054tony

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#8
  • Nov 12, 2023
  • #8
Solved. New pump in and started right up. The old sock on the pump had also fallen off and disintegrated in my hand.
 

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3054tony

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Nov 9, 2023
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Nov 12, 2023
#9
  • Nov 12, 2023
  • #9
2000xp8 said:
Not sure what comes with a new tank, but make sure you have new seals and sending unit. I'd also consider the tank to filter hose.
And without a doubt a tank strap stud kit. That's a real mess and i would not be going back in there again.
Click to expand...
Kind of in a tight spot for now so just ended up cleaning everything the best I could. It has to go to a storage unit for a couple months until our new house is finished. All the above is definitely on the list to replace as soon as we get situated. I did do the new seals that came with the sending unit and pump.
 
Last edited: Nov 12, 2023
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