Your fuel level sending unit is probably going bad. It is in the top of the fuel tank and the fuel tank must be removed to change it.
The fuel sending unit is part of the fuel pump in the gas tank and both must be replaced to fix the problem. The fuel pump is part of the 100,000 mile warranty.
You may have a faulty fuel gauge sending unit in the fuel tank.
chec the plug in on your sending unit on your gas tank
I have a 1996 Monte Carlo Z34, and I've noticed that the fuel gauge reading will bounce around whenever the car is tipped up or down as the fuel sloshes around in the gas tank.
hole in fuel sender gauge float
want to replace fuel gauge with aftermarket gauge, need to keep stock sending unit, will a 230 ohm gauge work
If the fuel gauge isn't working on a 1999 Chevrolet Blazer it could possibly be because the float is stuck in the fuel tank. I had this problem when I got my 99 blazer, the float and sensor for the fuel gauge is on the fuel pump which is in the fuel tank to keep it temperature regulated. I had to replace my fuel pump, which ended up going bad on me, and after it was replaced the gauge works just fine.
One reason for a gauge not working is a broken part either in the fuel tank or between the fuel tank and the dashboard - keep looking
Need to check fuel pressure with a gauge first. Then check fuel pressure regulator. Need to check fuel pressure with a gauge first. Then check fuel pressure regulator. Need to check fuel pressure with a gauge first. Then check fuel pressure regulator. Need to check fuel pressure with a gauge first. Then check fuel pressure regulator.
That, or the gauge is going. Or a loose wiring connection. I'd bet on the last.
bob bob loo bob bob loo
The alternator is on it's way out.