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How many amps are the fuel pumps

  • Thread starter Thread starter mob
  • Start date Start date Jun 23, 2005

mob

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Jun 23, 2005
#1
  • Jun 23, 2005
  • #1
Im making a fuel cut off switch, i got a 12v switch and 25amps, will this be enough? or will it blow the switch? thanks
 

jrichker

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Jun 23, 2005
#2
  • Jun 23, 2005
  • #2
mob said:
Im making a fuel cut off switch, i got a 12v switch and 25amps, will this be enough? or will it blow the switch? thanks
Click to expand...
Should be plenty. The wiring is only rated to carry 15 amps.

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 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.
 
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