As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN LEVEL FLIGHT AT FL400 THE LT ENG BEGAN VIBRATING BADLY. POWER WAS REDUCED, BUT THE VIBRATION CONTINUED & THE ITT BECAME VERY HOT. THE ENG WAS THEN SHUTDOWN MANUALLY. R & R PRESS REGULATING & SHUTOFF VALVE IAW G450 CMP 361106 & G450 CMP 361215. OPERATIONS CHECK & LEAK CHECK OF VALVE GOOD.