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No Power To The Fuel Pump


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#1
huntfam_3

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[FONT=Courier][SIZE=7][COLOR=red]Here is my problem, I replaced the fuel pump, fuel pump strainer and inline fuel filter, and now I cant seem to get any power to the new fuel pump. I check the electrical lines with a tester and nothing. Any suggestions would be greatly appreciated.

#2
snailman153624

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Probably blew the fuse or fried a relay....check in the big fuse box under the hood.

#3
jpit

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If you're having a hard time identifying the fuel pump relay, it's marked "circuit" relay on my '97. May be the same on yours :smile:

#4
huntfam_3

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My father-in law has a 97 626, so I borrowed the EGI Main Relay and tested it. Nothing. I have checked all the fuses I could find. All of them but the AC were good.

Per the Tech Manual I took the cover off the Diagnostic box and using a jump wire connected the F/P to the NEG. ^_^ But still nothing.

#5
jpit

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Some of our cars require you to go to the 'start' position and not just the 'on' position in order for the relay to pick.

Also in my car the FP relay is the 'circuit' relay, not the 'EGI main' relay. Maybe it's labelled differently for your year.

Maybe a poor ground on the Fuel pump. Have you tried bringing 12 volts to it by just wiring it to the battery as a test? You may want to put a fuse inline while testing if you think there may be a short.

#6
huntfam_3

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I tried it in Start and on. The only thing I havent tried is a direct conection. How would I go about doing that, Just undoing the wires from the fuse box? -_-

#7
jpit

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Are you able to get to the connector back at the fuel pump? I would try it there. If you can get to the conector and disconnect it then you could use your meter to measure the resistance of the pump motor by measuring between the outside connector wires. There should be some resistance. It shouldn't be shorted and it shouldn't be an open condition. Most motors measure in the single-digit range of ohms such as 4 to 8 ohms.

Another place you should be able to measure the resistance of the motor is by pulling the 'circuit' relay out and placing your leads on the 2 connector leads that go to the pump. When you pull the relay the 2 leads are the ones closest to the fender. Here's a pic of mine. I just went out and measured it. Mine was 6 ohms.

#8
huntfam_3

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Ok. I will try that once I leave work today. I sure appreciate all the help and will keep u informed if that doesn't work.

#9
huntfam_3

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what setting was your meter on?

#10
jpit

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Just the ohms scale. Mine is a digital auto-ranging meter. It determines the range. If you have one that you have to set manually, then set it to the X1 ohms(resistance) scale.

#11
huntfam_3

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Still haven't tried the direct connection. Had to visit family this past weekend and show off my new son. He is only 3 weeks old.

#12
Chthonian

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Still haven't tried the direct connection. Had to visit family this past weekend and show off my new son. He is only 3 weeks old.

congrats!

back to the problem... did you check the wires for stripping??? could be grounding out

#13
huntfam_3

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i did check. the only places the wire is showing is where I used a ohm meter to test the wires. Other than that every thing check out alright. B)

#14
jpit

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i did check. the only places the wire is showing is where I used a ohm meter to test the wires. Other than that every thing check out alright. B)

Did you measure about 6 ohms as shown in my picture? If so then for now you can say your pump is ok and also the wire going from that point on the fuse box back to the pump. Time to start checking if you have 12 volts supplied to it via the fuel pump relay. B)

#15
jpit

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Here's the fuel pump relay circuit. This way you can see that when you go to start your car the relay is energized with 12volts on Terminal 'A' and Ground on Terminal 'B'. This will tie Terminal 'C' to 'D'.




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