Gas gauge not operational .....low fuel light on......half tank of fuel present.......car starts normal 2003 hyundai santa fe

Ur evap fuel unit in tank is bad..probly need new solenoid..get fixed soon cause it keeps floodn engine n will ruin it

with out further info I would guess sending unit on fuel gauge is bad,that would be located in fuel tank

The fuel level sensor is inside the tank. Sometimes you can get lucky and it will start working again on it's own, but normally you will need a shop to drop the tank and install a new fuel level sensor. Often it is included with the fuel pump itself.

Average for a V6 engine 2 wheel drive model is 20mpg. That is 20 miles per gallon US.
If you have an 18 gallon tank, you could expect 180 miles on a half tank of fuel. Again, this is US measurements.

Well anything is possible.
The low fuel sensor for the warning light is part of the gauge in the tank. As long as the gauge works and the light does not come back on I would not be concerned. You may want to watch your mileage to make sure you don't run out of fuel if the gauge does fail.

Initially I would agree fuel pressure had dropped off after shut down. This fuel filter is a sock screen attached to the fuel inlet tube of the fuel pump and is located inside the fuel tank with the fuel pump. This screen is rarely the cause. You'll need a fuel pump pressure gauge to verify the low fuel pressure at start up. Caution, sometimes this low pressure isn't a faulty pump, sometimes it's a poor wiring connection to the pump motor. An analog amp meter can verify if there is fluctuation/ing current flow to the fuel pump. A fluctuating current flow could mean poor connections, or could mean the pump has/is gone/going bad.

happened to mine, also a 2003--needed a new part in the gas tank some vacuum seal thing or something that regulates the pressure in the gas tank

no gas tank must be removed

could be a weak fuel pump or could be fuel filter

dear friend-take note that you have two feul floats in the tank one works from full to half and the otherside from half to empty.