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**Sheepdip** · 10-21-2022, 11:42 PM

A couple of days ago I filled Otis up with some $6.59 a gallon fuel and noticed my fuel gauge read way past full. I kept an eye on it and it wasn't going down so today I rolled him up to the barn pulled the ground wire from the sender and grounded it out and the gauge went immediately to empty.

I checked the Ohm's thru the ground wire to the gauge and got about 47 Ohms which is ballpark for the resistor across the back of the fuel gauge. Gauge should be good as tested and has always been fairly accurate.
I then cleaned the contact on the grounding wire hooked it back up to the sender and no difference.

Tomorrow I'll pull the sender make sure it's not hung up, and/or check Ohm's to verify it is indeed the sending unit.

About a year ago I experienced a similar issue but after burning a 1/4 tank or so it returned to and has been normal until it reared it's ugly head again, at the time I just wrote it off as a hung up float arm.

10-21-2022, 11:42 PM	#3373
Sheepdip Senior Member Join Date: Nov 2018 Location: Waterford California Posts: 2,408	Re: What did you do to your truck today.The 3rd chapter A couple of days ago I filled Otis up with some $6.59 a gallon fuel and noticed my fuel gauge read way past full. I kept an eye on it and it wasn't going down so today I rolled him up to the barn pulled the ground wire from the sender and grounded it out and the gauge went immediately to empty. I checked the Ohm's thru the ground wire to the gauge and got about 47 Ohms which is ballpark for the resistor across the back of the fuel gauge. Gauge should be good as tested and has always been fairly accurate. I then cleaned the contact on the grounding wire hooked it back up to the sender and no difference. Tomorrow I'll pull the sender make sure it's not hung up, and/or check Ohm's to verify it is indeed the sending unit. About a year ago I experienced a similar issue but after burning a 1/4 tank or so it returned to and has been normal until it reared it's ugly head again, at the time I just wrote it off as a hung up float arm.