As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURN BACK INITIATED DUE TO MULITPLE ENGINE INDICATION FLUCTUATIONS FOR EXHAUST GAS TEMPERATURE, OIL PRESSURE, OIL TEMPERATURE AND OIL QUANTITY. STATUS MESSAGE EICAS DISAGREE ON THE GROUND AFTER LANDING. NO EMERGENCY DELCARED. SYSTEM DEFERRED 64215, MEL CATEGORY A. REMOVED AND REPLACED EICAS COMPUTER IAW MM 31-41-02. OPERATIONAL CHECK GOOD. DEFERRAL 64215 CLEARED.