Is there a cure for the unreliable fuel gauge in the +4 ?
The cheapest and most effective solution is to simply ignore it and go by mileage. I can get 350 miles out of my 4/4, so I fill up every 250 miles knowing that I've got plenty of reserve.
Tim H. 1986 4/4 VVTi Sport, 2002 LR Defender, 2022 Mini Cooper SE