Could be a bad sender (in tank), gauge (in dash) or the wire (gray IIRC). If you have a spare sender lying around you can disconnect the pigtail at the bumper and plug the sender in and see if does the same thing.
Ground the wire going to the gauge. The gauge should read empty. If it does, the problem is the sending unit or bad ground at the tank. If it doesn't you could have a bad connection at the dash.
I am watching this thread I am having same issue. I am planning on dropping my aftermarket tank and just start grounding the unit, ground wire whatever to see if it will work.
I detached the pigtail and the tank and connected them thru 2 diff. wires but grounded the black one thru another wire to the frame and the gauge went to empty. So where is the tank ground at?
I found out it was the little board that the float contacts with the thin wire wrapped around it held on by those two screws was bad. Someone prolly knows the name. I just swapped that from an 88 cutlass and it works fine.
Read this post wrong, i thought they ment a "fuel rail" gauge...
The Dashboard fuel gauge what's this thread's about.
While back,Mine use to stick at 1/2 tank,If i hit the dash,it'd go back to reading right.
was the gauge it's self that was shorted