What was found
N1 INDICATION: ERRATIC WHEN N1 IS ABOVE 9 PERCENT, RT ENGINE. N1 FLUCTUATIONS AFTER T/O. AIR COND PACKS SURGING SOUNDS, SHORTLY AFTER NR 2 ENG. EPR AND N1 STARTED FLUCTUATING NR 2 EPR +- . 07 TO 08 EPR NR 2 N1,+- .3 TO .4. *S/D* AFTER THE HPSOV WAS INOP IN THE CLOSED POSITION, THE ENGINE STILL SURGED-EPR N1, N2. BLEED PRESSURE FLUCUATED WITH THE HPSOV LOCKED CLOSED. THE PRSOV WAS REPLACED AND NO SURGES WERE REPORTED AFTER THE ENGINE RUN-UP. NO ADDITIONAL SURGE OCCURRENCE WERE REPORTED DURING THE FOLLOWING MONTH.