Dozy
wasn't there an SAS MD-80 where the autothrottles firewalled (and destroyed) the engines following ice ingestion?
a bit more complicated, but the engines did increase in thrust by virtue of an aircraft auto-system command unbeknown to the pilot and were not retarded by the pilot to clear the engine surging,
Other similar MD-80 ice events where throttles were not retarded by the crew even though the aircraft systems did not advance them in those cases.