Simple fix is usually a new oil pressure sending unit. It could be unplugged or the line broken somewhere. If none of these are the case, it's probably a bad gauge and will need to be replaced.
Bad oil pressure sending unit?
Your temp gauge is a very simple circuit with few things to go wrong. Your temp sensor may be bad, the gauge maybe bad, or the connecting path may be bad. Sometimes if you have taken the gauge pack out, it does not seat right when it is reinstalled. The connection inside the dash is all pressure and prayer.
A bad sending unit in the gas tank.
It is most likely the oil pressure sensor, located on the front of the engine block near the oil filter. There is also a slim possibility that the gauge in the instrument cluster is defective.
Reverse airflow feels a chamber inside the gauge and reads the pressure equal to the inside of the tyre its that simple. Same for air compressure, when the pressure is applied it seals the valve on the gauge end then back pressure fills the chamber inside the gauge when you release the gauge from the tyre valve the pressure has gone!!
Get a rod done.
More then likely you need to replace the Thermostat.
it will work but you have to use a pressure regulator in line so you can set the fuel pressure down to 6 psi. for the carburetor
The fuel tank pressure sensor is for the EVAP system. It has nothing to do with the fuel gauge sending unit.
Pressure Indicator is any instrument that indicates pressure. Pressure Gauge is also a type of pressure Indicator. It is a mechanical device. Pressure indicators can work on mechanical deflection (in case of pressure gauge) or Piezo electric effect, change in capacitance, change in inductance etc. These are generally digital type instruments.
The problem could be a dirty sensor or the sender is no good.
1984, Corvette the fuel gauge stays at 1/2 full all the time. Plaese help.