Nissan Pulsar 2013: Inaccurate fuel gauge

Having read Jim's complaint about his fuel gauge in his Nissan Pulsar our only complaint with our 2013 Pulsar ST is a very inaccurate fuel gauge. Within 70 kilometres of filling up it will indicate quarter of a tank gone. I can also run the gauge down into the red and have the kilometres-to-empty light flashing zero, but then it only takes 32 litres in what is meant to be a 55-litre tank. When we queried it at the Nissan dealer we were told there was nothing they could do as it was because of the shape of the fuel tank.