What was found
THE PILOT ONBOARD NOTED AN INDICATED REDUCTION IN OIL PRESSURE AFTER REACHING HIS CRUISE ALTITUDE AND CONFIGURATION. THE OIL PRESSURE INDICATION DROPPED FROM THE NORMAL RANGE TO THE YELLOW CAUTIONARY RANGE. THE INDICATION CONTINUED TO FLUCTUATE IN THE LOW SIDE CAUTIONARY RANGE WITH OCCASIONAL INDICATION IN THE RED WARNING RANGE. THESE INDICATIONS WERE ACCOMPANIED BY THE AUDIBLE CAUTIONARY AND WARNING TONES. THE PILOT DID NOT OBSERVE ANY OTHER NON-STANDARD ENGINE INDICATIONS, OIL TEMP, RPM, MANIFOLD PRESSURE. THE PILOT MADE THE DECISION TO DIVERT FROM THE INTENDED DESTINATION TO MAKE A PRECAUTIONARY LANDING DUE TO THE UNKNOWN STATUS OF THE OIL PRESSURE. UPON INVESTIGATION BY MAINTENANCE, FOLLOWING THE UNSCHEDULED LANDING, IT WAS DETERMINED THAT ENGINE WAS PRODUCING PROPER OIL PRESSURE. THE OIL PRESSURE SENSOR WAS REPLACED WITH A NEW UNIT AT WHICH TIME THE IN COCKPIT OIL PRESSURE INDICATIONS RETURNED TO NORMAL.