Fuel Gauge

The pointer of the fuel gauge is moved by the magnetic fields of two coils. The coils are at right angles to each other. Battery voltage is applied to the "F" coil and the circuit divides at the opposite end of the coil. Another to ground through the variable resistor of the fuel sender.

When the tank is low, the resistance of the sender is low.A large flow current passes through the "E" coil and the fuel gauge sender resistor. This moves the pointer towards "E" on the scale. When the tank is full, the sender resistance is high . More current now flows through the "F" on the scale .With two coils operating the pointer, the gauge is not affected by changes in the vehicle's electrical system.

The Oldsmobile gauges cluster (UH8) uses a fuel antislosh circuit that needs to be reset in order to get an immediate reading of the gauge. This fuel antislosh circuit is reset by cycling the ignition switch from OFF to ON.