What was found
FOUND NR 1 ENGINE WITH ECONOMIC FAULT MESSAGE 77-20871, TOP LT EGT SIGNAL IS OUT OF RANGE. ACFT GROUNDED. ENGINE 1 ELECTRONIC ENGINE CONTROL SHOWS NO RECENT AND FAULT HISTORY FAULTS LAST 10 FLIGHTS. IAW FIM 77-21, TASK 804, T495 PROBES CLEANING REF AMM 77-21-00, BEFORE CLEANING S1 TO S4 GOOD. S2 TO S3 WERE OUT OF TOLERANCE. AFTER CLEANING S1 TO S4 AND S2 TO S3 GOOD. ELECTRONIC ENGINE CONTROL TEST REF AMM 73-21-00 GOOD. ENGINEERING REQUEST ACCOMPLISHED - T49.5 PROBE AND EGT SYS INSPECTED, CLEANED CONNECTIONS. OPS GOOD. GROUND VERIFICATION SUCCESSFUL.