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Discussion Starter · #21 ·
If your reading across the correct connector locations, your meter is indicating that the fuel level potentiometer is not connected which is why the gauge does not work. You will have to access the connector on the fuel pump assembly and continuity check each wire from the H-15 (or under seat connector) to the pump assembly connector and figure out which wire is open and repair it.
Is it possible the sending unit we had put in was faulty because i believe it was used

Edit: i was wrong it was new but could it have been damaged when installed?
 

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Was the complete fuel pump assembly replaced or just the sending unit?

Be aware that most of the aftermarket fuel pump assemblies do not come with a compatible electrical connector. A fuel pump assembly pig tail connector is supplied and the installer cuts off the OEM connector and splices in the pig tail connector. Does your fuel pump assembly have a OEM connector or a cut and splice pig tail connector?
 

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Discussion Starter · #23 ·
Was the complete fuel pump assembly replaced or just the sending unit?

Be aware that most of the aftermarket fuel pump assemblies do not come with a compatible electrical connector. A fuel pump assembly pig tail connector is supplied and the installer cuts off the OEM connector and splices in the pig tail connector. Does your fuel pump assembly have a OEM connector or a cut and splice pig tail connector?
The complete fuel pump assembly was replaced and it had a cut and splice pig tail connector
 

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Is there continuity between under seat connector pins and the fuel pump connector pins for all four wires?
 

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Discussion Starter · #27 ·
Is there continuity between under seat connector pins and the fuel pump connector pins for all four wires?
I tested between the fuel pump connector and the H-15 connector i know for a fact that the blue/yellow orange/green and black/orange they all had continuity i wasnt sure how to test the solid black wire because of i didn't see it going into the H-15 connector for me to test
 

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The Black wire is the Fuel Pump motor ground.The resistance between the Black wire and chassis ground sb less than 1 ohm.
The connector pin out is as show in this image
The Delphi connector/Fuel Pump assembly pin out is as shown.
The Fuel Pump motor should be Pins Gray (B) and Black (C)
The Sending Unit pins should be Violet (A) and Orange/Black trace (D)
What resistance do you read across these pins on the Fuel Pump assembly with the Delphi connector not attached?

Cable Composite material Wire Electrical supply Font
 

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I have been looking at the image you posted of the spliced wires and it appears the two wires for the sending unit are reversed,
 

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Discussion Starter · #31 ·
The Black wire is the Fuel Pump motor ground.The resistance between the Black wire and chassis ground sb less than 1 ohm.
The connector pin out is as show in this image
The Delphi connector/Fuel Pump assembly pin out is as shown.
The Fuel Pump motor should be Pins Gray (B) and Black (C)
The Sending Unit pins should be Violet (A) and Orange/Black trace (D)
What resistance do you read across these pins on the Fuel Pump assembly with the Delphi connector not attached?

View attachment 120947
On the fuel pump assembly between pins C and B for the fuel pump motor its reading basically no resistance but there is continuity. But on the pins A and D on the fuel pump assembly there is no continuity.
 

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B and C is the Fuel Pump motor, the resistance is typically very low, probably 3 ohms.
A and D is the sending unit, The resistance has to be between 80 and 290 ohms depending on the fuel level. You will have to pull the pump assembly out of the tank and troubleshoot the sending unit.
 

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Discussion Starter · #33 ·
B and C is the Fuel Pump motor, the resistance is typically very low, probably 3 ohms.
A and D is the sending unit, The resistance has to be between 80 and 290 ohms depending on the fuel level. You will have to pull the pump assembly out of the tank and troubleshoot the sending unit.
Well my parents got impatient and just went ahead and ordered a new fuel pump assembly so hopefully if i understand everything right then i should just be able to install the new fuel pump and sending unit and everything should work fine?
 

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I just read an earlier post where you said you already replaced the sending unit, did you replace the entire fuel pump assembly or just the sending unit?
 
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