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Discussion Starter · #1 ·
My new fuel sender arrived today and I thought I would bench test everything before putting it in.

The sender is showing 1 ohm - 31 ohm range.
So I crawled under the car and hooked up the brown wire and ground and then had my wife watch the gauge. I could only get the gauge to go from E - 1/2 full.

Thinking maybe the brown wire was bad I ran a new wire. Still the same results (if not worse range was E - 1/8 tank).

I followed the gauge troubleshooting steps at http://www.eastcoastchevy.com/X6tech/tech_gas.html
With sender wire in the air and ignition turned on, the needle stays below E. If I briefly ground it then let it in the air the needle goes to full. If I ground it again the needle goes to E.

I also checked the power to the gauge 11.8 volts.

Any ideas what may be going on here?

Thanks much!
Pete
 

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The wire off the sender should peg full whilst in mid air, go to E when shorted to the frame.

You need to make sure that the two wires under the cluster are in the right position, gas guage ignition on drivers side, gas guage sender on pass side,
you may also ground the tank with a star washer



 

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I tested my gauge the same way, but I added wire to the brown wire and then ran a ground wire to the ground side of my battery and was able to sit in the seat and watch the gauge.

This sounds a bit crazy but use some insulator like cardboard or paper to hold the sender and float with to make sure you don't get yourself in the circuit.
 

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Trifive Automotive Electrical Wiring Expert
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With sender wire in the air and ignition turned on, the needle stays below E. If I briefly ground it then let it in the air the needle goes to full. If I ground it again the needle goes to E.
Pete
That sounds like the gauge is sticking intermittently. Try repeadedly grounding and ungrounding the sender wire to see if it may free up the gauge movement. The gauge may need cleaning and lube.
 

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Discussion Starter · #5 ·
I used a Potentiometer and found the following:
E = 0 ohm
1/4 = 20 ohm
1/2 = 30 ohm
3/4 = 40 ohm
F = 50 ohm

I'm guessing that either the gauge needs some oiling [Hitting it with more that 30 ohms gets the needle to move beyond a half tank] or the gauge windings are bad.
 

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I used a Potentiometer and found the following:
E = 0 ohm
1/4 = 20 ohm
1/2 = 30 ohm
3/4 = 40 ohm
F = 50 ohm

I'm guessing that either the gauge needs some oiling [Hitting it with more that 30 ohms gets the needle to move beyond a half tank] or the gauge windings are bad.
Keep us posted :tu
 

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Trifive Automotive Electrical Wiring Expert
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27,022 Posts
With sender wire in the air and ignition turned on, the needle stays below E. If I briefly ground it then let it in the air the needle goes to full. If I ground it again the needle goes to E.

[Hitting it with more that 30 ohms gets the needle to move beyond a half tank]
Pete
How about hitting it with a rubber mallet? :)
From your test, the gauge appears to be intermittent (sticking).
Also note that when bench testing a gauge, it needs to be in the same position as it is in the car. The weight of the needle movement affects the reading.
 
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