I'm curious if my 64 F85 fuel gauge is reading correctly. When the key is off the tank reads full, then when I turn it on, the needle moves over to the halfway mark. All the cars I've ever owned were opposite, I'm curious if this is typical for the F85 or maybe the wires for my gauge are crossed?

 

Does the gauge measure the level of fuel in the tank correctly? If so, then I wouldn't be concerned with where it parks itself with the key off. Sending units are just 90 ohm resistors with power supplied when the key is on.

When the key is off, the resistance is technically infinite, and the gauge should go well past "F." But it doesn't because, I believe, there is some kind of damper to hold it in place when there is no power. But, as I said, the bottom line is, if the gauge reads correctly when the key is on, there is nothing to be concerned about.

 

Thanks, im just curious if that is typical for this car. I haven't had to put any fuel in it yet so not sure how close it is to reading the actual level.