Topic: Bouncing fuel gauge
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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I looked thought the archives but could not find any discussion on the exact problem I am having.
My fuel gauge reads OK ( Full is Full, Empty is Empty)
The problem is that needle bounces during acceleration, braking, cornering.
Is this typically the sending unit or the dash gauge?
Thanks
Tom
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Lifetime MemberGreensburg, IN - USA
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Vette(s): Previous: 1984 Coupe, 1988 Maroon Coupe, 1989 Coupe, 2001 Roadster Present: 1967 Stingray Roadster, 1976 Stingray Coupe, 1989 Roadster..
Not for sure Tom but it sounds like a ground or loose wire somewhere. My guess would be at the tank since it is the most prone to the elements for corrosion.
I would start in this area to take and see if anything appears broken corroded or loose. Some of the other guys will chime in and add to this thread as well maybe one of them has had this experience.
I would start in this area to take and see if anything appears broken corroded or loose. Some of the other guys will chime in and add to this thread as well maybe one of them has had this experience.
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Duncanville, TX - USA
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This problem is most likely due to a bad resistor/"buffer" on the circuit board, behind the fuel gauge. If the gauge shows the correct amount of fuel, but is just flopping back & forth while driving, that's where I would look.
All sending unit floats will bounce around some. The "buffer" is there to even out, or average the reading at the gauge.
All sending unit floats will bounce around some. The "buffer" is there to even out, or average the reading at the gauge.
Joel Adams
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I had the same problem a couple years ago with the '81. It would read great as long as you weren't moving or the tank was packed full of fuel.
It turned out to be the gauge. I had checked out the ground and wiring to the sending unit previously.
I was in conversation with another member here trying to figure out which item was bad, he explained that the fuel gauge itself is supposed to be like a damper to slow down the respond of the sending unit that is usually moving around rapidly while driving.
78-82's use the same gauge. I think I got mine through Bair's. They were the best price. AC Delco P/N 6432523
Good luck, and let us know what you find when you get 'er fixed.
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Lifetime Member #26
Borgeson Steering Box
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Lifetime Member #26
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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