Technical Fuel gauge help

I have a 55 F100 with stock gauge and sending unit. Im a rookie when it comes to wiring. The gauge has been working fine. The other day the wife and i took the truck for a spin and now the gauge reads full all the time when the truck is on. If you turn it off it goes down to E. I've checked the lead wire and everything looks good. I pulled all the screws out of the sending unit and the gauge goes back to E. When I went to put them back in, some had no effect and some would send the gauge back to F. I believe I have a grounding issue and think I just need a new gasket between the tank and sender. Can any electrical guys tell me if I'm on the right track? If not can you steer me in the right direction.

Thanks in advance.

 

Pull out the sending unit and check the resistance range from full to empty with an ohm meter and go from there.

Sent from my SM-T350 using The H.A.M.B. mobile app

 

Could your wife be pranking you?

 

We used to buy a guy gas...really confused him.

 

If you disconnect the wire from the sending unit the gauge should read empty. If you ground that wire, the gauge should go to full. Sounds like your sending unit might have an internal short.

Lou

 

thank you, thats exactly what's happening.

 

lol

 

lol