Wrxnz

Hi guys my fuel gauge has just started playing up had just over quarter of a tank then I noticed it dropped to empty then slowly went back up but then drops to empty again after abit and repeats tryed doing some research which lead me to the fuel pump area was about to take it out for a nosey but wasn\'t sure if I had a gasket or rubber seal Any help would be great on what I could do to fix this issue Cheers