Question: 1981 Oil pressure. Bad sender?

[FactoryC3]

When I start my engine the oil pressure reads just below 40 and in about 1 minute it jumps up over 40 and goest up and down with rpm...buy not over 50. I checked the connection and reseated it but no change. Is it the sending unit?

 

[LLC5]

It could be a sending unit, harness, gauge, etc, but to be sure that your oil pressure is indeed good you need to remove the sender and install a mechanical gauge with a hose attached and check your oil pressure readings. The proper test procedure is to prove that the engine oil pressure is good before spending any money on parts.