What was found
AFTER ENGINE START WITH BLEEDS AND PACKS ON AND ALL OTHER SYSTEMS SWITCHES POSITIONED NORMAL (AI OFF). THE NR 1 ENGINE INDICATED 88.8 AND NR 2 ENGINE INDICATED 88.0 N1. WHEN THE NR 1 BLEED AIR SWITCH WAS MOVED TO OFF, THE NR 1 ENGINE N1 VALVE DID NOT CHANGE. WHEN THE NR 2 ENGINE BLEED AIR SWITCH WAS MOVED TO OFF, THE NR 2 ENGINE N1 INDICATIONS READING 88.0. NORMAL OPS ESTABLISHED. ACFT GROUNDED. ACCOMPLISHED FIM 34-61, TASK 839. NO DEFECTS NOTED. REPLACED THE LEFT FLOW CONTROL AND SHUTOFF VALVE IAW AMM 21-51-01. OPS CHECKED GOOD. LEAK CHECKED GOOD. . NO DEFECTS NOTED.