[folivier]

A few days ago we filled up with diesel and after a few miles I noticed the fuel gauge was reading 0.
I just pulled the vanity panel off the tank to access the sender and pulled the sender wire off and the gauge stayed on empty. Then I grounded the sender wire and the gauge went to full.
So what does this mean? bad sender unit or bad gauge?

[HoosierDaddy]

bad sender

[Chester Stone]

Forest, if you have the polished stainless outer shell, I can give you some pointers on how to remove the sending unit without removing the tank. One mistake I made was not knowing that the new sending unit had a pin that has to be removed for it to work. Let's discuss tomorrow.

[Retro]

Forest, if you ground your sender wire and the guage goes to full its your sender not the guage, by doing that you proved your guage is working

[folivier]

Thanks, Newell is bringing a new sender to me.

[77newell]

Forest: did you check the ground wire at the sender. On the 93 coach the sender has two wires; one for the signal to the dash gauge and one that goes to ground on the chassis steel. It could be just the ground wire isn't passing current. Bypassing it temporarily to see if the gauge changes may save you the hassle of pulling the sender. I would also check the wiring between the sender and gauge by grounding the signal wire at the sender. All these tests will help verify whether it's the sender.