I feel a bit awkward posting here as I've made no contributions to this community so far (just registered) and I'm not really a car guy. But here it goes anyway.
I've a 1995 525i and overall the car runs great. It has fairly new spark plugs (did them in...oh, I think May) and I keep up on the oil, etc. The only issue seems to be that when the fuel gauge tells me the car is about 3/4 of a tank low on gas (one notch before the R) the car will predictably hesitate when accelerating over 40mph and, if pushed past that speed, shut off. To fix this I typically just turn the car right back on after coasting to the berm. Once restarted the engine light will turn on and everything will work fine. Obviously this freaks me out a bit and I've always just gone immediately to the gas station after such an incident but never did I feel that I was actually out of gas or anything like that. If the car isn't pushed over 40mph then I can typically sneak by with just receiving the engine light at the 3/4 mark, and again, I've always just gone to the gas station at that point.
Like I said before, I'm no car guy, so I really have no clue what this could be. As far as I know the car has been doing this since I bought it in April of last year. I suppose it isn't a huge issue but it is annoying and is probably a sign of something more serious. I'm not sure. Any guesses would be warmly welcomed.