I have the same problem. The low fuel light used to come on anywhere from 1/4 tank to 1/8 tank level. I found I could go about 30 miles without trouble after that so I got in the habit (for 4 years!) of hitting the trip meter when the light went on and then being sure to fill up within 15 miles if I could. Well, recently, it only made it to 10 miles and I was out o' gas. First time in my life. Then a few weeks later - much to my shame, I ran out of gas and the light hadn't even come on. I had the shop look at it - the light is fine (turns on with the key), gage seems to work fine. My new method is fill 'er up at 1/4 tank. My get out o' jail free card for running out of gas has been used up so I don't think the hubby is going to rescue me again!
