Pro Comp gas gauge not working correctly

[ZoSoIV]

hey guys just bought a 1970 Z-28 , RS on the resto they used Pro Comp gauges and the gas gauge isn’t working correctly ... when full it shows just over a half tank and empty it shows around a quarter tank ... I’m trying to pin down if it’s the gauge or the gas tank float ... what should I look at first ? Thanks

 

[[email protected]]

Check the voltage, and see if the correct voltage is at the gauge , if it is then the junk in the trunk/tank is acting up

 

[ZoSoIV]

Ok thanks

 

[Twisted_Metal]

The gauge is an ohm meter.
It measures resistance in the circuit through the sending unit.

It may simply be a mismatch between the gauge and sending unit resistance range.

Try to find out the model of the gauge to find its intended ohm range.

If I remember correctly... the sending unit should be 90 Ohms full and 0 Ohms empty.

 

[ZoSoIV]

Thanks