As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING TAKEOFF A VIBRATION AND LOW EGT WAS FELT ON THE LT ENGINE. TAKEOFF POWER WAS STILL ACHIEVED FOR THE FLIGHT. THE AIRCRAFT RETURNED TO LAND. BOTH THE DENSITY AND DIFFERENTIAL CONTROLLERS WERE FOUND TO HAVE OIL LEAKS. THE OIL WOULD CONTAMINATE THE AIR PASSAGES IN THE FCU AND CAUSE THE LOSS OF POWER AND VIBRATION. THE CONTROLLERS WERE REPLACED AND RUNUPS COMPLETED WITH NO FURTHER PROBLEMS. (TC NR 20070928003)