As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TEST FLIGHT FROM CGF, LEFT ENGINE OIL PRESSURE DECREASED INTO THE RED ARC, LEFT ENGINE WAS SECURED. AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REMOVED OIL PUMP PART NUMBER 3102614-02 SERIAL NUMBER 1GAT57 IN ACCORDANCE WITH MAINTENANCE MANUAL AND INSTALLED OIL PUMP PART NUMBER 3104289-01 SERIAL NUMBER 8W081. OIL WAS SERVICED. FUNCTION AND LEAK CHECK WERE SATISFACTORY. AIRCRAFT WAS RETURNED TO SERVICE.