2003 Saturn L200

SOURCE: check gauges light

Possible bad guage, bad wiring, or bad sending unit. Check each one independently of each other, start with wiring first, then sending unit.

SOURCE: fuel gauge not working on 2005 ford mustang

Sending unit is in gas tank. usually as an assembly with the electric pump. These aren't cheap either, If you know a mechanic you can trust ask him how much to install a new one, I can get them wholesale for less than two hundred dollars, but of course retail probably more like 250.00 Hope this helps you!

SOURCE: gas gauge reading empty even when tank is full

Usually if the gas gage does not work yes it is true it may be the sensor if it is electronicly controlled. the sncor will more than likley be in the tank. here is how to remove your gas tank.

1. Before servicing the vehicle, refer to the precautions section.
   
2. Relieve fuel system pressure.
   
3. Drain the fuel tank.
   
4. Remove or disconnect the following:
   
   • Negative battery cable
     
   • Fuel filler and vent hoses
     
   • Fuel tank skid plate
     
   • Fuel tank wiring connectors
     
   • Fuel supply and return lines
     
   • Fuel tank
     
   • Fuel pump assembly
     Fuel pump assembly mounting
     

1. Install or connect the following:
   
   • Fuel pump assembly
     
   • Fuel tank. Tighten the bolts to 27 ft. lbs. (36 Nm).
     
   • Fuel supply and return lines
     
   • Fuel tank wiring connectors
     
   • Fuel tank skid plate
     
   • Fuel filler and vent hoses
     
   • Negative battery cable
     
2. Start the engine and check for leaks.
   

SOURCE: gas gauge reads empty but tank acts like it's full

I also have a 04 with a 1.8L. same problem. I took the fuel regulator off. It is a black box behind the rear tire under car. It only has 2 bolts to take off. After that there is a couple of vent hoses from the tank going to this box. Unplug them and 1 electrical connection. The electrical connection and one vent is connected to a T connection on the box that you can unplug by twisting on the T. Take that T off and look inside where you unplugged the hose on this T. There is a spring and a little plunger inside this tube. The plunger gets stuck. I took a little screw driver and some PB blaster and worked that plunger back and forth a couple dozen times and it unfroze. Put it back together gassed up just fine. I did not look but I was told regulator can be replaced for 200$. But a can of blaster is cheaper.

SOURCE: 2002 Chevy Suburban: Fuel gauge reads empty, tank is half full

Youre gauge is controlled by a plunger in the fuel tank which is attached to the sensor and the fuel gauge. it sounds like when the plunger goes down half way its either getting stuck down lower then it should. Needs replacing. Any mechanic can do this install for you.