Codigo4

Just wanted to know if anybody else has had this problem and if anyone might know how to fix it.

It started when I wasn't driving my car much so I wasn't filling the tank all the way up, I thought nothing of it when the fuel light was on all the time. When I did finally fill the tank up, it wouldn't shut off, then about after a week of driving around with the fuel light on all the time, it finally turned off, but now when the fuel light would normally come on it doesn't, it has been about 3 months and I haven't seen the light come on, when I know the tank is low. Thought the light isn't burnt out because when I go to start the car all my idiot lights light up. I think I covered it all. Any help would be nice.

Thanks,
Cody