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Fuel 86 gt fuel pump won't turn off

  • Thread starter Thread starter 86 mustang 5.0
  • Start date Start date Apr 27, 2024
8

86 mustang 5.0

New Member
Apr 27, 2024
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0
1
Wisconsin
Apr 27, 2024
#1
  • Apr 27, 2024
  • #1
I parked my 86 gt 5.0 in the garage, drove it right in. It sat for about 2 months. I went to start it and noticed (key on engine off) the fuel pump wouldn't shut off. It should shut off after a few seconds of priming. I located the fuel pump relay under drivers seat. I found one of the pins was broke off, so I thought that's the problem so I replaced it. Once installed I turned the key on and the pump kept running like before. So I turned off the key, but now when I turn the key on the fuel pump doesn't even turn on. I am able to get the pump to turn on if I ground the wire in the diagnostic connector by the windshield wiper motor. But the pump won't turn off until I turn the key off. Anyone have a problem like this?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Apr 27, 2024
#2
  • Apr 27, 2024
  • #2
Check for codes, mostly to verify the computer is communicating
 
8

86 mustang 5.0

New Member
Apr 27, 2024
2
0
1
Wisconsin
Apr 27, 2024
#3
  • Apr 27, 2024
  • #3
General karthief said:
Check for codes, mostly to verify the computer is communicating
Click to expand...
Thanks for your help, however I'm not sure how to check for code on a vehicle this old.
 

85GTStangGuy

5 Year Member
May 19, 2021
1,001
625
133
Jax, Florida
Apr 28, 2024
#4
  • Apr 28, 2024
  • #4
86 mustang 5.0 said:
.... I'm not sure how to check for code on a vehicle this old.
Click to expand...


The easiest method may be with the following...

Amazon.com
 

FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
6,098
2,707
224
Vass, NC
Apr 28, 2024
#5
  • Apr 28, 2024
  • #5
Continuous priming can be the result of a bad computer.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,925
10,572
203
polk county florida
Apr 28, 2024
#6
  • Apr 28, 2024
  • #6
Here: https://stangnet.com/mustang-forums...des-from-eec-iv-in-86-95-5-0-mustangs.889006/
Should get you headed in the right direction.
 
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