What was found
DIAGNOSTICS REPORTED NR 1 ENGINE TREND DATA SHOWS EGT SCATTER AND DECREASE IN HOT DAY MARGIN. ALL OTHER PARAMETERS NORMAL. EGT INDICATION ERRORS ARE SUSPECT. ACFT GROUNDED. PERFORMED ALTERNATE DEACTIVATION PROCEDURES FOR L/E SLATS AND NR 1 ENG THRUST REVERSER IAW AMP CHAP 5 SEC 5-07-01. PROCEEDED TO CLEANING ALL OF THE EGT SYSTEM CONNECTORS IAW AMM 70-70-01-200-801-F00 AND PERFORMED GOOD OPS CHECK. NR 1 ENG T49.5 PRIOR: S1- 90.14 S2- 50.65 S3- 58.89 S4- 120.39#1 ENG T49.5 POST: S1-40.46 S2- 26.80 S3- 26.75 S4- 56.74.