As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE 1 SURGING IN BOTH AUTO & MAN THRUST. N2 FLUCTUATING +/- 2 PERCENT. AIR RETURN LANDING WEIGHT 135.5-ACCOMPLISHED FAULT ISOLATION FOR EPR SURGING IAW TSM 71-00-00-810-832 PRESSURE CHECKED SENSE LINES TO PRV NO FAULTS NOTED IAW AMM 36-11-00-810-900. REMOVED & REPLACED PRV (4001HA) ON #1 ENG LEAK & OPERATIONAL TEST SATISFACTORY IAW AMM 36-11-52 PB401