Just curious...did the oil pressure read correctly prior to the diagnostics?
We ran the boat while the computer was hooked up. The Port Eng. Oil Pressure reading was stuck on 50psi. while all other parameter readouts were in motion as they should be. After replacing the sender, The computer oil pressure numbers read normal and fluctuated with power settings as it should. The analog oil pressure gauge on the dash was reading normal before and after, not very accurate. Hope this helps.