As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB THROUGH 20000 FEET, THE #2 ENGINE OIL PRESSURE WAS DROPPING TO 14-15 PSI RANGE. ACCOMPLISHED CHECKLIST AND BROUGHT ENGINE BACK TO FLIGHT IDLE. ENGINE NOW SHOWED 44 PSI. EMERGENCY DECLARED AND RETURNED TO FILED. LANDING UNEVENTFUL. REMOVED FROM SERVICE. REPLACED THE ENGINE HARNESS.