As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
#1 ENGINE ROLLED BACK IN CRUISE BUT FULL POWER AUTHORITY WAS REGAINED AT A LOWER ALTITUDE. ENGINE CONTROL LIGHT ILLUMINATED AFTER LANDING. / REMOVED & REPLACED THE ELECTRONIC ENGINE CONTROL UNIT IAW M/M 73-21-60. RAR 53220 PN: 1853M33P06 SN OFF: LMDN5132 SN ON: LMDN9459