As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) IN CRUISE FLIGHT CREW NOTICED NR 1 ENGINE FUEL FILTER CLOG LIGHT ON. AIRCRAFT RETURNED TO BASE. MAINTENANCE REMOVED NR 1 ENGINE LP AND HP FUEL FILTERS FOR INSPECTION. LARGE AMOUNTS OF CONTAMINENTS FOUND IN LP. FILTERS WERE REPLACED. GROUND RUN CARRIED OUT. THIS IS THE SECOND OCCURANCE OF FUEL CLOG WARNING. 1ST AFTER 25 HRS FOLLOWING C-CHECK INSP. THE SECOND 1000HRS FOLLOWING C-CHECK. (TC NR 20060606006)