Gas Gauge trouble shooting

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Dave Whittick
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Gas Gauge trouble shooting

#1 Post by Dave Whittick »

I've read through a lot of threads but needed a little clarification.

6 volts to the gauge when the key is on.
Gauge freshly restored by North Hollywood Speedometer. Always reads empty.
New sender from Stoddard reads 198 ohms full and 10 ohms empty.
Gauge does not jump to full if I touch the green sender wire to ground.

The needle in the gauge jumps, ever so slightly, when I turn the key.

Safe to assume the gauge is faulty?

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Al Zim
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Re: Gas Gauge trouble shooting

#2 Post by Al Zim »

Dave: why don't you call Aaron about your situation. We are indebted to you for your patronage. al
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Dave Whittick
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Re: Gas Gauge trouble shooting

#3 Post by Dave Whittick »

Al Zim wrote: Fri Mar 17, 2023 3:09 pm Dave: why don't you call Aaron about your situation. We are indebted to you for your patronage. al
I will call them if my troubleshooting is sound. Just looking for confirmation.

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Ken Tuvman
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Re: Gas Gauge trouble shooting

#4 Post by Ken Tuvman »

Dave Whittick wrote: Fri Mar 17, 2023 2:59 pm I've read through a lot of threads but needed a little clarification.

6 volts to the gauge when the key is on.
Gauge freshly restored by North Hollywood Speedometer. Always reads empty.
New sender from Stoddard reads 198 ohms full and 10 ohms empty.
Gauge does not jump to full if I touch the green sender wire to ground.

The needle in the gauge jumps, ever so slightly, when I turn the key.

Safe to assume the gauge is faulty?
I’d check continuity from both points of contact from gauge to sender - also - I had to buy a couple sending units as first one I bought was defective- there is a way to test it but I forgot how it’s done.
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Mike Wilson
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Re: Gas Gauge trouble shooting

#5 Post by Mike Wilson »

I've set up some pigtail wires to check the sending unit removed from the gas tank. I connect to the sender wiring in the trunk and slowly move the arm of the sender while watching the gauge.

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Ken Tuvman
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Re: Gas Gauge trouble shooting

#6 Post by Ken Tuvman »

Dave - after troubleshooting if you decide to try another sending unit make sure you get one that is compatible with your 356 - you didn’t mention year & model of your car - in my case, a 356B T5 super, I found a Dansk unit on EBay that solved that problem.
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Dave Whittick
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Re: Gas Gauge trouble shooting

#7 Post by Dave Whittick »

Ken Tuvman wrote: Fri Mar 17, 2023 7:15 pm Dave - after troubleshooting if you decide to try another sending unit make sure you get one that is compatible with your 356 - you didn’t mention year & model of your car - in my case, a 356B T5 super, I found a Dansk unit on EBay that solved that problem.
My sending unit tested fine. I can watch the resistance increase and decrease within factory limits. Big test is grounding the green wire that connect to the sender. This should make the needle jump to full. Mine does not. Def the gauge at this point. Looking for a replacement.

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