As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6549 - CLE-IAD - MADE AN UNSCHEDULED LANDING DUE TO LEFT ENGINE TORQUE FLUCTUATIONS AND SURGE. AIRCRAFT RETURNED TO GATE WITH NO FURTHER INCIDENTS. MAINTENANCE CLEANED LEFT ENGINE STRAIN GAUGE CANNON PLUG AND SWAPPED TORQUE SIGNAL CONDITIONER BRIDGES, OPS CHECK OK. AIRCRAFT WAS RELEASED AND RETURNED TO SERVICE. (M)