Fuel Gauge

[BadBird]

When the gas tank on my 64 is full the gauge reads between 1/2 to 3/4. I read on a Ford website that when the tank is full the sending unit puts out a certain amount of ohms and when empty the ohms are different. I will admit I don't have a clue what or how to check that.

Then, is there a way to adjust the internal float or whatever, to fix the problem? Or, is it a problem with my sending unit not putting out the correct ohms? Wrong type sending unit?

Badbird AKA Larry

[Jeff W]

I can't remember... Are you running a stock gauge and sending unit in your bird?

[Luva65wagon]

Resistance is measured between the connector on the float and a good ground. It will be hard to do anything with in the car with a tank full of gas other than finding what the resistance (ohm reading) is supposed to be at FULL and see if it is. If it's right, then the gauge is wrong. Here's a little tech page on checking some of the gauges.

http://www.falconparts.com/ford-falcon-auto-parts/pc/Dash-Instrument-Testing-d30.htm

Also, make sure the tank has a good ground path. Resistance increases through bad grounds.

[SmithKid]

Not sure if I'm remembering correctly; does the little voltage regulator (resister?) behind the dash affect the guages? Kinda seems like it might, but maybe my OLD memory is getting faulty, too.