What was found
AIR TURNBACK/DECLARED EMERGENCY, PASSING 10,000' WITH CLIMB THRUST AT 95% N1,THE #1 ENGINE STARTED SURGING BETWEEN -5 TO-10% N1.SHORTLY THEREAFTER #1 N1 ROLLED BACK TO NEAR IDLE THRUST. ENGINE INDICATIONS APPEARED NORMAL. ENGINE BLEED AIR WAS ON AND AC PACKS WERE IN AUTO. ENGINE ANTI-ICE WAS OFF. R&R #1 ELECTRONIC ENGINE CONTROL PER AMM.