Re: Fuel Gauge
The fuel level sender is in the tank with the pump. The entire thing can be replaced as one unit. It is called the fuel pump module.
CAUTION: Do not remove magnetic gauge pointers; the gauge cannot be recalibrated.
The magnetic fuel gauge consists of four primary coils, one of which is wound at a 90-degree angle to the other three.
The coils form a magnetic field which varies in direction according to the variable resistance of the fuel level sensor.
A primary magnet, to which a shaft and pointer are attached, rotates to align to this primary field, resulting in pointer position.
The bobbin/coil assembly is pressed into a metal housing which has two holes for dial mounting.
The fuel level sensor (part of the fuel pump module) changes resistance according to the level of fuel in the fuel tank, which varies the current flow through the gauge. The pointer position varies proportionately to the current flow.
The pointer of the magnetic gauge remains in relatively the same position when the ignition switch is turned to OFF.
There is no adjustment, calibration or maintenance required for the fuel gauge.
Low Fuel Level Warning
Instrument Cluster Gauge Amplifier
The conventional instrument cluster contains an instrument cluster gauge amplifier which provides a delay to the fuel gauge/temperature assembly to prevent the fuel gauge pointer from fluctuating as a result of excessive movement in the fuel tank.
The instrument cluster gauge amplifier has additional circuitry to turn on a LOW FUEL warning indicator when the fuel gauge/temperature assembly shows approximately 1/16 tank of fuel remaining.
The instrument cluster gauge amplifier is designed to prove out the LOW FUEL warning indicator. The instrument cluster gauge amplifier is a small printed circuit board which latches into a pocket on the back of the instrument cluster.
The electrical connections for ignition, ground, input from fuel sender, output to fuel gauge/temperature assembly and low fuel warning output (where equipped) are made through a spring-type connector on the instrument cluster gauge amplifier to the instrument cluster printed circuit on the instrument cluster.
There are no provisions for calibration or adjustment of the instrument cluster gauge amplifier.
Unfortunately to actually test the gauge it becomes quite involved and requires an ohm meter and knowledge of wire diagrams.
PM me if you want more info.