Your Sorento's fuel system allows the vehicle to run by feeding gasoline from the tank to the engine. Four components --- the fuel tank, pump, filter and injector --- comprise your vehicle's fuel system. Gas gauge malfunction occurs when the fuel tank sending unit no longer properly communicates with the dashboard gas gauge.
Fuel Guage Function
The fuel gauge system consists of the gas gauge and gas tank sender. Turning on the Sorento's ignition provides power to the gas gauge, causing current to flow between the two coils connecting the gauge with the gas tank sender. When your tank nears empty, the float measuring the amount of gas in the tank will go to the bottom, so most of the current flows directly to the tank sender, where it passes on to a ground wire. More fuel placed in the tank causes the float to rise, sending more current to the operating coil of the dash gauge, allowing the needle to move closer to the full mark. Electrical friction from the gas tank sender guides the current to either the tank sender or the dash gauge.
A loose ground wire connected to the tank sender causes the majority of gauge malfunctions.
If turning on the ignition does not cause the dash gauge needle to move when the tank has gas, then an interruption exists that is keeping the battery current from reaching the gas gauge. A defective gas gauge or tank sender will keep the dash gauge needle from moving in either direction when turning the ignition on or off.
A lower than accurate gas gauge reading suggests a connection issue exists between the gas gauge and tank sender, while a higher than accurate gas gauge reading suggests a wiring malfunction in the tank sender unit.
A defective gas gauge unit will cause the dash gauge to read empty regardless of the amount of gas in the tank.
Helpful Repair Tips
Check to ensure that all wires are tight and that connections are clean of any dirt or rust. This will eliminate or help narrow down the cause of the gauge malfunction.
If malfunction persists, contact your local mechanic to schedule maintenance.
Kia Sorento repair manuals are available for purchase online for as little as £6 each (as of 2010).