branndon_b
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mike, i asked him and all he knows is that they said that they ran him an independent wire, i guess from the fuse box somewhere, i dunno exactly.
3 bad fuel pumps in a row, unbelievable!
- Thread starter Korn
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Korn
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Well I just checked the voltage and its at 11.29 volts. Is that enough or am I low on voltage? If its low I wonder where it could be. Thanks for all the help guys.
---------- Post added at 05:10 PM ---------- Previous post was at 04:32 PM ----------
OK OK OK, I did another voltage test. The first test I hooked the black lead on my multi meter to the black wire on the fuel pump plugin then I hooked the red test lead to the gray wire on the plugin and got 11.29 volts. Then I hooked the black multi meter lead to the chassis for a ground and hooked the red multi meter lead back to the gray wire again and got a reading of 13.33 volts.
On the instruction manual of one of the fuel pumps it says that the black wire is the fuel pump ground circuit, So I thought maybe the ground is bad somewhere so I ran a jumper wire from the black wire to the chassis for a ground. It didnt like that, everytime I hooked it up while the yukon is running it would cause the engine to stumble briefly then it would run fine as long as I didnt move the connections. This got me thinking, why would it do this. So I then hooked up my test light to the black wire (fuel pump ground circuit) and the other end to the chassis ground, the fricken light came on the test light, not very bright but it came on. WTF would that be.
---------- Post added at 05:10 PM ---------- Previous post was at 04:32 PM ----------
OK OK OK, I did another voltage test. The first test I hooked the black lead on my multi meter to the black wire on the fuel pump plugin then I hooked the red test lead to the gray wire on the plugin and got 11.29 volts. Then I hooked the black multi meter lead to the chassis for a ground and hooked the red multi meter lead back to the gray wire again and got a reading of 13.33 volts.
On the instruction manual of one of the fuel pumps it says that the black wire is the fuel pump ground circuit, So I thought maybe the ground is bad somewhere so I ran a jumper wire from the black wire to the chassis for a ground. It didnt like that, everytime I hooked it up while the yukon is running it would cause the engine to stumble briefly then it would run fine as long as I didnt move the connections. This got me thinking, why would it do this. So I then hooked up my test light to the black wire (fuel pump ground circuit) and the other end to the chassis ground, the fricken light came on the test light, not very bright but it came on. WTF would that be.
ok, to clarify, the ground line from the harness, to the chassis ground, and you are getting voltage? Can you put the multimeter in that line and see for sure? The ground line in the harness on one probe and the other probe on the chassis shoudn't give you any voltage. Can you do a continuity test on it?
992dr
Full Access Member
When you swapped out to a new pump, did you ever replace the factory harness with the supplied harness?
I'm asking because that was the issue with the factory harness.
I bought a Delphi, it came with a harness, hooked it up according to the directions and I have had no problems since.
That fuel gauge fluttering is the stepper motor.
I'm asking because that was the issue with the factory harness.
I bought a Delphi, it came with a harness, hooked it up according to the directions and I have had no problems since.
That fuel gauge fluttering is the stepper motor.
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Korn
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I went and hooked up my multi meter from the black wire and tested it for voltage, it was at 0.13 volts. So apparantly there is voltage going to it and Im sure there shouldnt be.
Yes i did install the supplied harrnes plug that came with the napa pump. I did this about 3 years ago. The plug is the same as what is on the new pumps that I have been trying. I wonder if I hooked something up wrong. Or how about this idea, shoud I cut the black wire and run a direct wire from the pump to the chassis?
Yes i did install the supplied harrnes plug that came with the napa pump. I did this about 3 years ago. The plug is the same as what is on the new pumps that I have been trying. I wonder if I hooked something up wrong. Or how about this idea, shoud I cut the black wire and run a direct wire from the pump to the chassis?
In theory, yes. Cutting the black wire and running it to a chassis ground should work fine. I would like to say though that I am guessing here. I don't have the wiring schematics for your vehicle and I don't know how it is wired. I did similar work on my former truck, which was a 97 Sierra. I would give it a shot and see if it doesn't improve the situation. Maybe even try out one of the other pump brands to see if they work properly that way.
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Korn
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Im going to give it a try.
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Korn
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Well gents heres the results, I started it up and let it idle. I then cut the black wire and the yukon shut off, just as I suspected it would do cause there is no ground wire to complete the curcuit. I then left it cut and ran a ground wire from the black wire on the conector and hooked it to the chassis. She fired rite up, I then checked the voltage and it up around 12.30 volts.
I then hooked everything up the way it should be and I only get 11.32 volts and the test lite will come on as previous mentioned. I am suspecting that the ground wire coming from the relay is shorted somewhere. Does all this make sense to you. I also tested my make shift ground wire for voltage and there was none.
I then hooked everything up the way it should be and I only get 11.32 volts and the test lite will come on as previous mentioned. I am suspecting that the ground wire coming from the relay is shorted somewhere. Does all this make sense to you. I also tested my make shift ground wire for voltage and there was none.
SunlitComet
OBS Jedi-Do Good
The relay has a positive voltage output not ground. G404 is the grounding point for your tank pump and is located above the pump on the frame rail. It might just need some cleaning. The frame to battery ground could also cause a voltage drop when using the frame as your ground.
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