Fuel gage reads backwards
#1
Fuel gage reads backwards
With power on and key on the fuel gage needle points to full ( the tank is 1/2 full, measured with a woden stick) When I disconnect the (-) battery wire and wait 1-3 minutes the needle slowly starts going from full clockwise towards empty.(the needle goes under bottom of the gage, not across the top down to empty....
I checked the sending unit by Barry K. instructions and it is ok..( put the ohm meter between the two bare terminals at the sender the pushed the float un nad down and got 4-90 ohms...)
With the battery connected, the needle starts moving counterclock wise as lonmg as the key is on. I checked the voltage at the gauge with a meter and got 11.6volts, checked the voltage at the sender got the same voltage. Checked the ground at sender OK and at the gage. I was not working on any of the fuel system ...
Thanks for any help... Chuck
I checked the sending unit by Barry K. instructions and it is ok..( put the ohm meter between the two bare terminals at the sender the pushed the float un nad down and got 4-90 ohms...)
With the battery connected, the needle starts moving counterclock wise as lonmg as the key is on. I checked the voltage at the gauge with a meter and got 11.6volts, checked the voltage at the sender got the same voltage. Checked the ground at sender OK and at the gage. I was not working on any of the fuel system ...
Thanks for any help... Chuck
#3
#5
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If your gauge wiring seems right, then maybe your car is actually making fuel, out of vapors extracted from the air. You might be the owner of the first old Corvette to have a negative carbon footprint!
#6
In checking my gauge, I had a long thin piece of wood and I cut a groove in the end which will fit over the edge of the float in the tank. With the tank 1/2 full, you can see the float in the tank and look forward and see the gas gauge on the dash.
Turn the key on (disconnect the ballast so you don't burn the points) and using the stick you can see what the gauge does as you push down on the float. Maybe the wires are on backwards?
Don
Turn the key on (disconnect the ballast so you don't burn the points) and using the stick you can see what the gauge does as you push down on the float. Maybe the wires are on backwards?
Don
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#8
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sounds like a bad gauge
Chuck,
sounds like a bad gauge to me. That is, assuming that you have the wires connected correctly at the sending unit (Pink to "I" and brown/tan to "S"). I chased my fuel gauge problems for a while and found that BOTH my gauge and sending unit were faulty. Here a quick check that should tell you if the gauge is working.
1. Disconnect the brown/tan wire at the sending unit. With power and ingition on, the gauge should show one extreme (memory tell me that is should be "full", but I've slept since then.)
2. now ground the brown pigtail to a known good ground and the gauge should read the other extreme.
If the gauge does not behave this way, then it is in need of repair/replacement. The fact that the gauge goes from full clockwise to empty without power tells me that the gauge is faulty. When my gauge came back from repair it showed about 1/2 full without power.
Here is a link to my troubleshooting of my gauge issues.
sounds like a bad gauge to me. That is, assuming that you have the wires connected correctly at the sending unit (Pink to "I" and brown/tan to "S"). I chased my fuel gauge problems for a while and found that BOTH my gauge and sending unit were faulty. Here a quick check that should tell you if the gauge is working.
1. Disconnect the brown/tan wire at the sending unit. With power and ingition on, the gauge should show one extreme (memory tell me that is should be "full", but I've slept since then.)
2. now ground the brown pigtail to a known good ground and the gauge should read the other extreme.
If the gauge does not behave this way, then it is in need of repair/replacement. The fact that the gauge goes from full clockwise to empty without power tells me that the gauge is faulty. When my gauge came back from repair it showed about 1/2 full without power.
Here is a link to my troubleshooting of my gauge issues.
#9
Racer
We C1 guys got to stick together . So in that spirit , do it like the rest of us do it. Don't worry about it . Everytime you take the car out.. go to the gas station and fill up . That will guarantee you some mental tranquility and if the needle is pointing the wrong way or jumping up or down on forty miles of bad road , so what ?
I've tried to get mine perfect to no avail . The only time it's right is when it reads empty !
I've tried to get mine perfect to no avail . The only time it's right is when it reads empty !
#10
Race Director
When I replaced the wiring harness in my car they reveresed the wires in the plug for the fuel gage and it read backwards. I carefully pulled the terminals out of the plastic connector and reversed them and it worked fine. Check the leads per Spilt_Window's earlier post, especially if you've replaced the wiring harness.
Dan
Dan