fuel gauge nova problem

i just got my nova and the fuel gauge is not working at all. it's on "E". where to start?? (and yes there's fuel) are there some common problems to look for?? thanks!

my fuel gauge the past few weeks has been acting weird, it seems that everytime that i parked on a hill when i started the car the gauge would stay on full for about 10 minutes of runtime then go back to the correct level, but just now i just drove about 4 hours and i even tried adding fuel with...