What was found
#1 ENGINE IS ALERTING FOR OIL FILTER DELTA PRESSURE INCREASE AND APPROACHING OIL FILTER BYPASS INDICATION. GROUNDED - YES. COMPLETED TSR STEPS 1, 5, 6, NO DEBRIS NOTED. TSR STEPS 2 & 3 COMPLETED, NO CONTAMINATION FOUND IN OIL FILTER. COMPLETED TSR ALL STEPS NO CONTAMINATION FOUND. REMOVED AND REPLACED OIL FILTER DIFFERENTIAL PRESSURE SENSOR IAW B737-9 AMM 79-35-01.