What was found
RETURNED TO DEPARTURE. ENGINE 1 SURGE AT POWER REDUCTION ALTITUDE, 1000 FT EPR, N1, AND N2 ALL SURGING. N1 SURGING 1.2 PERCENT UP AND DOWN. TURNED AUTO THRUST OFF, NO HELP. FOUND STAGE 7B & 7C SOLENOID VALVES INOPERATIVE, FUNCTIONAL TEST FAILED IAW 7-32-53-700-010. R & R VALVES IAW AMM 75-32-52; RAN ENGINES TO FLIGHT IDLE N1 READINGS 34.3-34-.5; OPS NORMAL. OPS CHECK IF FMU NORMAL IAW AMM 73-22-52, OPS CHECK OF ELECTRONIC ENGINE CONTROL NORMAL IAW AMM 73-22-34; ACFT OK FOR SERVICE.