Fuel gauge issue..what could be the cause?
 

68 camaro, turned the car on the other day and the fuel gauge just pegged at what would be 3:00 on a round gauge. Way past full. It has worked fine until now. Stock 68 camaro gauge (original no tach). I assume it's a sending wire problem. Is the signal a negative or positive lead? Where are the problem areas to look for a short?

Thanks in advance for the help.

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funny that you say that cause mine did the same thing last week

check your wire for nicks that would cause it to go to ground on the body.most guages read ohms to ground

sender wire
 

Sounds like the driver coil is seeing all 12v; this could be due to an open in the sender wire. the 'signal' wire is a 0-90 ohm resistance that the sender creates, which changes the magnetic field that drives the needle (by virtue of changing the amount of voltage at the gauge coil). Sorry to dork out on ya... :(

what side of the car does the sender wire run?

90% sure that means you have an open. You can easily check the sender with an ohm meter at the tank before you tear apart the car. You should see between 0-90 ohms depending on how much gas you have in the car. If that checks out you know it's a connection, broken wire, or gauge issue.

fuel gauge
 

It runs down the driver's side...it's the tan wire that protrudes through the trunk pan next to the fuel pipe (to the left looking down). The brown wire is the ground, which needs to be good, or your sender won't do a damn thing.

How are your rear lights? The fuel sender gets it's ground from the same circuit...if they aresketchy, your fuel gauge will follow suit.

great info. thank you all. will check it out on wednesday. will post an update.

Actually the brown wire is power and you have a seperate ground that is near one of your tail light housing.

update
 

the brown wire IS '+'.

I disconnected the sender plug, connected 12v to a short light and touched the wire that is the sender wire going to the gauge and receive a complete circuit. therefore, the wire is obviously grounded somewhere right? or am i seeing this wrong. could the gauge be showing a ground? the wire from the actual sender is showing 30'ish ohms so i assume the sender is OK.

help