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

kill switch problem???

  • Thread starter Thread starter the pony boy
  • Start date Start date Aug 4, 2007

the pony boy

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Apr 19, 2002
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#1
  • Aug 4, 2007
  • #1
i installed a kill switch a while back in my car and i was wondering if i should have grounded it?it just a toggle switch the cuts the power to the fuel pump.should i have used a differnt switch.the reason i ask is i have a slight (100 rpm)idle surge i have been chasing for a while and i have done almost every trick to fix it to no avail.the next is to check the alt and eiminate the kill switch. phil
 

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Follow this tech note for the best way to wire a fuel pump kill or anti-theft switch...

On 86- 91 cars the fuel pump relay is under the driver’s seat, 92 and later cars, the fuel pump relay is under the Mass air duct on the passenger fender well.

Note that the wire colors changed in 1991, so there are two different descriptions.

86-90 model cars:
Cut the red/black wire going to the fuel pump relay. Splice a 16 or 18 gauge wire into the wire and connect it to one side of the switch. Connect the other side of the switch to the other end of the red/black wire going to the fuel pump relay. When you are done the switch should be in the middle of the spliced red/black wire that goes to and comes from the fuel pump relay. Using the control side of the circuit allows you to use light gauge wire and light duty switches. There is less than 1 amp going through the circuit, so you don’t have to worry about voltage drop across the wiring depriving the fuel pump of electrical power.
See http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model wiring diagrams.


91-93 model cars:
Cut the Lt Blue/Orange wire going to the fuel pump relay. Splice a 16 or 18 gauge wire into the wire and connect it to one side of the switch. Connect the other side of the switch to the other end of the Lt Blue/Orange wire going to the fuel pump relay. When you are done the switch should be in the middle of the spliced Lt Blue/Orange wire that goes to and comes from the fuel pump relay. Using the control side of the circuit allows you to use light gauge wire and light duty switches. There is less than 1 amp going through the circuit, so you don’t have to worry about voltage drop across the wiring depriving the fuel pump of electrical power.
See http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model wiring diagrams.

See "Surging Idle Checklist for help with all your idle/stall problems. The first two posts contain all the updates to the fixes. I continue to update it as more people post fixes or ask questions.
 

the pony boy

Founding Member
Apr 19, 2002
358
0
16
10512
Aug 4, 2007
#3
  • Aug 4, 2007
  • #3
my cars a 93 and i spliced a green wire? under the drivers seat and mounted the switch in the center console.the wire was bigger than 16-18 gauge wire more like 12-14 gauge.as far as the idle goes the car isnt driven often just really sits around waiting for the finishing touches but when i do drive/ move it is when i notice the idle problems.ive checked/cleaned replaced amost every possible culprit just exploring other possible causes. thanks phil
 

the pony boy

Founding Member
Apr 19, 2002
358
0
16
10512
Aug 4, 2007
#4
  • Aug 4, 2007
  • #4
by looking at the diagrams it looks like i spliced the feed for the inertia switch. phil
 
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