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I have gotten some excellent help and advice so far from this forum it has been great!
I have a fuel gauge on my '69 98 that is stuck somewhere in the middle. I have not done any investigating on this issue and wonder if anyone has a starting point for me.
The car runs beautifully, odometer and speedo work, just trying to sort out some details .
I imagine the float is stuck in the tank but before I go removing anything I figured I'd see if anyone has a solution.
Just to be clear regarding being "stuck". Do you mean the needle "remains" in the middle position both with the car in the ON running position AND when the car IGN is turned to the OFF position?
Lots of threads (using the Search feature) regarding fuel gauge issues. I'll point you to one such thread for a quick review. Try this to see "if" the needle moves at all. Chance it's mechanical (in the gauge itself) or electrical.
Here is another well written thread you might read to gain a better understanding of troubleshooting your issue. Obviously, you should be looking to see "if" the gauge will move at all.
I ordered the CSM. Has not arrived yet.
the gauge is stuck at about 1/4 full. I noticed a tiny amount of movement when I turned the key but very very little.
I found a ground wire just above and in front of the tank, cleaned it but still no improvement. I can't seem to locate the power wire from the tank. I guess the manual will give some insight but wondering where the power wire for the sender is located
I looked at the 1969 A-Body wiring diagram (located in your CSM when it arrives), it is a TAN 20GA wire. What I'm not sure of is the routing of that wire for a 1969 98 - sorry. Later models (at least 1971) the TAN wire came up from the top of the back of the fuel tank, through a rubber grommet in the trunk floor on the RH-side of the trunk latch and plugged into the Fisher Body wiring harness.
Two diagrams. One from the 1969 PIM (Product Information Manual), the other from the 1971 PIM. Again, I'm not clear on the exact routing. It appears different between 1969 & 1971; although, there were also improvements in the actual wiring diagrams themselves so I'm not clear (again) where the actual TAN 20GA wire emanates from the fuel tank on the 1969 98.
1969 PIM Fuel Gauge Wire Lead 1971 PIM Fuel Gauge Wire Lead
Haven't had much time this week with the 98 but I was able to determine the gauge is working by grounding out the gauge wire in the trunk.
Im assuming since the gauge goes back to about 1/4 full when plugged and stays there, that there is a problem with the float or sender in the tank.
Haven't had much time this week with the 98 but I was able to determine the gauge is working by grounding out the gauge wire in the trunk.
Im assuming since the gauge goes back to about 1/4 full when plugged and stays there, that there is a problem with the float or sender in the tank.
Yes, float or sender.
If you performed the tests as indicated in the URL link (thread) I provided above https://classicoldsmobile.com/forums...-right-146663/; and, the gauge needle can swing/move to E and then to F, you've validated gauge is working & gauge is not the issue.
In the simplest of terms,
Troubleshoot disconnecting the sending unit wire in the trunk near where it goes through the grommet and ground the gauge end. If the needle goes to E, the issue is towards the sending unit. If nothing happens, the issue is towards the gauge.
December 7th, 2023, 05:25 AM
