Fuel gauge needle is stuck on full

[Randy Hagins]

I bought a low mileage GN last May form a good friend of mine who is also the original owner. A few years ago he replaced the stock dash gauges with a Cyberdyne digital unit. Last Tuesday I removed the digital unit and installed the stock gauges. Once I turned the key on the fuel gauge went right to full. I just changed out the fuel pump, is it possible the fuel sending unit is bad?
Thanks in advance for the help.

Randy

 

[mikestertwo]

You have an open circuit to the sending unit or the sending unit is bad (open)

 

[earlbrown]

Only way to know for sure is to bust out the ohm meter.

You can get to the sending unit's plug under the bumper on the drivers side.

 

[Randy Hagins]

Great info! I appreciate the help. I’ll let ya know what I find out.

 

[Chuck Leeper]

What Earl said....

 

[Fat Nat]

Ground the sender wire in the back see if neddle moves. If it doesn’t then most likely it’s the connection in the dash make sure you have the dash screwed in tight and like the previous guys said make sure you don’t have a break from the back of the car to the dash plug with meter

 

[grass doctor]

https://www.turbobuick.com/threads/fuel-gauge-reading-wrong.404354/

worked for me mine
little different situation bc mine wasn't going all the way full
still not reading correctly

 

[Randy Hagins]

This is great info! I really appreciate it!! Thanks!