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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Fuel Pump Stays On With Key In On Position

  • Thread starter Thread starter sen2two
  • Start date Start date Feb 11, 2017

sen2two

I've been lubing and pulling it all morning
5 Year Member
Jul 18, 2013
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59
Feb 11, 2017
#1
  • Feb 11, 2017
  • #1
So normally. The fuel pump will prime for 2-3 seconds when I turn the key to the "on" position. Now it will stay on the entire time as long as I have the key in that position.

I'm not sure what caused it. But what I did today was wire in an Autometer digitial oil pressure gauge. And an Innovate DLG-1 Dual wideband. Somewhere during the wiring, I created this issue.

And as I'm writing this now, and going over the wiring in my head. The only thing I can think of is where I am getting my switched 12v source for the relay that powers the wideband. I ran it to the diagnostic plug that is next to the brake booster. I used a spade connector and just plugged it in to the spot that receives 12v with the key in the on position.

Could that be the cause? I'm at a friend's house now or I would just walk out and try...
 

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
Feb 11, 2017
#2
  • Feb 11, 2017
  • #2
Why wire it there? I didn't ask that question knowing if it was a good or a bad idea just that it's used for something specific, find a different place, I'm sure there are better places to plug it in, sounds like that was just easy peasy.
I'm sure one of the experts here can chime in.
@madmike1157 @a91what @jrichker
 

liljoe07

5 Year Member
Feb 18, 2009
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Cartersville,Ga
Feb 11, 2017
#3
  • Feb 11, 2017
  • #3
On a fox, there is no 12v to the diagnostic port. There is a fuel pump test terminal there. But it's technically a ground. And it can show 12v when the relay is not grounded. Find a different spot for your 12v switched source.
 
Last edited: Feb 11, 2017
Reactions: jrichker and a91what

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,570
203
polk county florida
Feb 11, 2017
#4
  • Feb 11, 2017
  • #4
I knew that!
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Feb 12, 2017
#5
  • Feb 12, 2017
  • #5
+1 if you want to use the switched power for the fuel pump relay, pick it up from the relay under the drivers seat.
 

sen2two

I've been lubing and pulling it all morning
5 Year Member
Jul 18, 2013
396
58
59
Feb 12, 2017
#6
  • Feb 12, 2017
  • #6
So removing that wire from that plug removes the fuel pump staying on issue.

Does anyone know a switched 12v source under the hood off the top of their head?
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Feb 12, 2017
#7
  • Feb 12, 2017
  • #7
switched 12v can be found at the fuse box under dash drivers side. a bullet connector will press in from the backside and stay in place very well. use the fused side of the radio, increase fuse by 5amps. this lets you make a clean install that's tucked out of the way and easily reversible.
 
Reactions: General karthief

sen2two

I've been lubing and pulling it all morning
5 Year Member
Jul 18, 2013
396
58
59
Feb 12, 2017
#8
  • Feb 12, 2017
  • #8
I moved it to get power from the radio 12v source since I don't have a radio. Works fine and now the fuel pump primes and shuts off as it should...
 
Reactions: General karthief
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