As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 6363 - LYH-IAD - ABORTED THE TAKEOFF DUE TO THE LEFT ENGINE TORQUE ROLLING BACK. AIRCRAFT RETURNED TO GATE WITH NO FURTHER INCIDENTS. MX PERFORMED CHECKS BUT COULD NOT DUPLICATE DISCREPANCY. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)