First, welcome to the forum.
Second, have you visually inspected the wiring to the fuel sending unit at the tank? From what you wrote it sounds more like an intermittent wiring issue and loose wiring/connectors can cause this kind of erratic fuel reading.
If the wiring is good then I'd suspect the sending unit itself is bad.
Mac
Second, have you visually inspected the wiring to the fuel sending unit at the tank? From what you wrote it sounds more like an intermittent wiring issue and loose wiring/connectors can cause this kind of erratic fuel reading.
If the wiring is good then I'd suspect the sending unit itself is bad.
Mac