This could be a problem with the wire coming from the oil sending unit. The threaded stud on the bottom needs to be clean and oil/dirt free. If the connector on the wire is stretched out, you can take a pair of pliers and crimp it back down, so it makes a nice solid connection.
I have included in the diagrams down below, the factory troubleshooting diagnostic flowchart for your cars Oil Pressure System. It will require you to install a Oil Pressure Test Gauge, but you should be able to rent this for free at your local auto parts store. Get back to us with what you find out.
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Monday, March 18th, 2019 AT 4:26 PM