What was found
MANIFOLD NR 2 OVER TEMP ILLUMINATED IN FLIGHT, TEMP WAS 215 DEGREES CELSIUS, PERFORMED CHECK LIST AND LIGHT WENT OUT. ENGINE DE-ICE WAS ON AT THE TIME. OPENED PYLON, CHECKED DUCTING FOR SECURITY, FOUND OKAY. PRE-COOLER VALVE FOR OPERATION WAS OKAY, REGULATING VALVE AND MUSCLE LINE OKAY, TEMP SENSOR MANIFOLD FOUND OKAY AND SECURED. FOUND AIR LEAKAGE ON NR 2 ENGINE FIREWALL SHUT OFF VALVE, SECURED CLAMPS AND OPERATES OKAY.