My car'* the same year and trim, and I have the same problem.
I took it to a shop after my engine died [blew an air uptake or some crap]
After they were done with it, the oil pressure would go low at idle. Sometimes touching that red line, and causing that god awful and constant dinging.
But as soon as I hit the gas, shot right back up to 40 PSI.
I wonder if there are any sensors that could go bad that would cause this problem? Or if they were improperly installed or something? They replaced the Oil Pressure Sending Unit too, which maybe is put in wrong?
I was gonna check the relief valve, but I don't want to take all the stuff off and risk putting it back on wrong and killing my engine.
But my pressure has been like this for about six months now, and the car is still running fine.
I just wish I could get a straight answer as to what'* wrong. Some people say bad sensors, some people say bearings, some people say relief valve; I'm not going to be keeping this car forever, I know that, but I just want the beeping to stop