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Discussion Starter #1
My fuel gauge moves around a little bit, like it has power, but tends to stay on 1/2 tank no matter how much fuel there is. I looked at the wire coming from the sender (in the tank), and saw that it is a single wire, but there are two wires coming from the front of the car (yellow w/white, and green w/white). The wire from the sender is connected to the yellow w/white wire. Am I missing a wire, or a ground?
 

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Discussion Starter #2
This is on a 69 standard. Anyone have their trunk open that can take a look?
 

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Ok, anyone know where I can find out about this?
 

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Dan,

I can't help with the wire colors, a wiring diagram would have them. I have the XR7 diagram, not sure if I have the standard, will look when I get to work. However, I can tell you this, for the fuel gauge there is only one wire for the gauge and the return is ground (body of the car). XR7 would have a second wire for the LF thermistor. If you pull the wire from the sender and ground it, the gauge should go to full. If it does not you have a problem with the wiring or gauge. If it does go to full, you either have a sender problem or a poor ground connection from the tank to the body, usually the sender. Hope this helps.

Regards,

Bob
 

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Update: Yellow-White is gas gauge wire and I have the '69 standard wiring diagram. PM me your email and I will send it to you (Monday if it is after 4 pm eastern today).

Regards,

Bob
 

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Discussion Starter #6
2012-06-23 18.37.06.jpg This is what the connection looks like to the sender...The green/white wire goes nowhere. Is this how it is supposed to be?
 

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Dan,

Green-white is for LF equipped cars per the wiring diagram I sent you.
 

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Discussion Starter #9
Dan,

Green-white is for LF equipped cars per the wiring diagram I sent you.
Oh, ok, so then the green/white wire is just extra on the Standard models. I tried taking the sender wire off and grounding it, but no change in the gauge at all. I guess my next step is to get the voltmeter out to test the wire. Thanks for your help XR7vert...Hope I can figure this out.
 

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Dan,

You previously mentioned that the gauge reads around 1/2. If this is true, at the very least, when you disconnect the sender wire, the gauge should go to empty. Is this happening? And, as I mentioned previously, if you ground the wire (harness side, not sender side) the gauge should go to full. This I assume is not happening but perhaps you did not ground the right thing?
 

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Discussion Starter #11
I ground the sender side, and nothing, the guage stayed at half.....also, when I unhooked the wire, no movement at all. I must have a problem behind the cluster.
 

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Dan,

The test is to ground the harness side (rather than the sender side), but if when you disconnect the wire from the sender there is no change in gauge reading, yes that's a problem further up the line.
 
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