New to the Forum -- I have a '97 Disco I TDi diesel, European spec, with 200,000 Km. Fuel gauge shows empty, with warning light lit, even immediately after fill-up. When about 400 Km is travelled (fuel tank about half full), then fuel gauge shows accurate after I've stopped for a break or end of the day. When I fill up again, gauge immediately shows empty when ignition key is turned on.
Appreciate your ideas.....
From Heidelberg Germany (Land of the Autobahn),
EuroBud

 

Sounds like a bad fuel tank sender unit going bad.
Mike

 

The other problem may be in the pick up tube sending a false reading. hope it helps. gotta love a rover. duboff