Author Topic: fuel guage readings in console  (Read 1902 times)

WaltZ

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fuel guage readings in console
« on: May 21, 2021, 05:02:26 PM »
when tank is full, guage reads considerably beyond full, believe it has maxed out.

when guage reads 1/4 and I refill it takes about 10 gallons

when guage reads nearly empty, it still takes 8-9 gallons

I am hesitant to run the guage down below empty to see how far it goes until there is about 3 gallons remaining.

It seems as though the guage could exceed  the empty as it does on the full.

If I remember correctly, my other one would go past full about 3/8", where this one the needle is nearly out of sight

Am I just splitting hairs here.

any ideas, or just live with it.
Thanks in advance
Walt

x55cam

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Re: fuel guage readings in console
« Reply #1 on: May 23, 2021, 07:43:42 PM »
Sound like either the sending unit is going bad or you may have a bad ground.  Check all your connections first. A volt/ohm meter would be handy.  the OHM range for the sending unit is 0-90. Not sure which extreme is what but if you fill the tank up take a reading at the sending unit side and see what it measures. You will have to disconnect the plug in the trunk.
Be careful about reading  health books. Some fine day you'll die of a misprint. - Markus Herz

69Z28-RS

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Re: fuel guage readings in console
« Reply #2 on: May 23, 2021, 11:57:14 PM »
Those gauges are notoriously inaccurate...   and are based onnon-linear sending units!
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Fred Mertz

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Re: fuel guage readings in console
« Reply #3 on: June 08, 2021, 12:52:25 AM »
I played with resistors to get my gauge to read more accurately.  I drained the tank and added 9 measured gallons of gas, then added resistors of varying value to the wire going to the sender until the gauge read half full.  Hope this helps. Dave

Henry Cloutier

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Re: fuel guage readings in console
« Reply #4 on: June 08, 2021, 10:35:34 AM »
Best guess is the sending unit. Mine would not read full no matter how hard I tried to coax gas into the tank. And regardless of how far down the gauge read I could never get more than about 9.5 gals in the tank. New sender fixed all issues. Once the tank is full now the needle is just above the full mark. If I remember correctly 90 ohms is full on this system.
Best regards,
Hank

 

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