light on and off at first is normal. level just finally gets low enough that the float stays far enough down for the low fuel light contacts to stay put. My '87 560SEL usually can go at least 20 miles after the light comes on. My usual place to fuel up is about 14 miles away so works out ok. I would not like to tempt Murphy too much more. At 4,130 lbs, I don't wanna push the car.