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Discussion Starter #1
I have a 1980 240D that the fuel gauge has always read full, since I bought the car about 3 weeks ago. PO stated the fuel gauge didnt work. What I have done so far. Removed the sending unit and disassembled. There was some real gunky stuff in the tube, and stuck on float. I cleaned all that out with brake cleaner, and shined the rod the float slides on, with emory cloth. All wires were intact, so I reassembled the sending unit and reinstalled. Turned key on, and fuel gauge is still pegged to full. Disconnected wire to sending unit. Turned key on, and fuel guage goes to half full, turn key off, it drops to empty. Checked the voltage going to sending unit via connectors at wired plug. One pin read 11.6 volts, one pin read 4.3 volts, and the other pin had no reading, so I surmised it was the ground.. I then checked the sending unit with my voltmeter in the ohms position. With one lead grounded, I touched the pin on the sending unit where the 11.6 volts would go, and it read 1(when I turn my voltmeter to ohms it reads 1 on the display, when I touch the leads together it reads 3 zeros). Next I touched the pin on the sending unit where the 4.3 volts would go, and it read all zeros. Lastly, when I touched the pin on the sending unit where the ground would go, it read all zeros. Now, can anybody shed some light on my problem, and direct me where to go next?:confused:
thanks,
Jim
 

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I would go to the local pick-n-pull and get a new oil/fuel/temp guage.
 

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Discussion Starter #3
79Mercy said:
I would go to the local pick-n-pull and get a new oil/fuel/temp guage.
No local junk yards in my area. 60 miles away from any major city, as I live in a rural area.
thanks,
Jim
 
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