B757 FLT CREW HAS ENG MALFUNCTION DURING CLB AND RETURNS TO DEP ARPT BEFORE ETOPS AIRSPACE.

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ON CLBOUT FROM HNL WITH CLB PWR SET FELT SOME YAWING MOTIONS WITH AUTOPLT ON. OBSERVED FLUCTUATIONS OF EPR FROM 1.30 TO 1.55 WITH ACCOMPANYING MINOR N1 FLUCTUATIONS. STANDBY ENG INSTS WERE IN AGREEMENT. NO OTHER ENG INSTS FLUCTUATED OR APPEARED ABNORMAL. THERE WAS NO POPPING OR BANGING. IN LOOKING FOR A CHKLIST FOR FLUCTUATING EPR THE MOST APPROPRIATE ONE WE FOUND WAS 'ENG LIMITS/SURGE/STALL QRC.' THERE WAS NO SPECIFIC CHKLIST FOR EPR FLUCTUATION. REFERRING TO IT WE TURNED OFF THE AUTOTHROTTLE AND RETARDED THE THROTTLE. THE FLUCTUATIONS STOPPED AFTER A VERY SMALL THROTTLE REDUCTION AND WE CONTINUED TO RETARD THE THROTTLE TO IDLE WITH NO MORE EPR FLUCTUATIONS. AFTER STABLE AT IDLE WE ADVANCED THE THROTTLE UP TO CRUISE WHERE IT REMAINED STABLE. UPON ADVANCING IT TO CLB PWR AGAIN THE FLUCTUATIONS RECURRED. SO WE RETARDED IT TO CRUISE AGAIN WHERE THEY STOPPED. THIS BROUGHT US TO THE NOTE IN THE QRC THAT STATES IF ENG ACCELERATES; TURN BLEED AIR SWITCH ON (WE HAD NEVER TURNED IT OFF); OPERATE ENG NORMALLY; LNDG AT NEAREST SUITABLE IS NOT REQUIRED; AND DO NOT ENTER ETOPS AIRSPACE. SINCE THIS FLT REQUIRED ENTERING ETOPS AIRSPACE THE DECISION TO RETURN APPEARED CLR. FURTHER TROUBLESHOOTING THROUGH DISPATCH WITH MAINT CTL WAS AN OPTION; BUT REACHING A TIMELY SOLUTION USING VHF (STAYING IN RADIO RANGE) BEFORE CONSUMING OUR MARGIN OF FUEL AT THE PET APPEARED UNLIKELY. ADVISED ATC AND DISPATCH AND TURNED BACK TOWARDS HNL. ELECTED NOT TO DECLARE AN EMER DUE TO ENG RUNNING NORMALLY AT CRUISE PWR AND BELOW. AND QRC NOTE STATING TO OPERATE ENG NORMALLY. HNL GAVE US AMPLE ASSISTANCE AND EXPEDITIOUS HANDLING. IF THIS HAD NOT OCCURRED WE WOULD HAVE DECLARED AN EMER IMMEDIATELY. ELIMINATED MAUI AS A DIVERT ARPT DUE TO SHORT RWY (INFERIOR OVERT LNDG PERFORMANCE); HIGH TERRAIN NEARER TO AND ON BOTH SIDES OF APCH COURSE; LESS FAMILIARITY WITH ARPT CONSERVING ALT AND AIRSPD TO AVOID HIGH PWR SETTINGS. LANDED IN VISUAL CONDITIONS OVERWT AT 217.0K ON HNL RWY 8L. SMOOTH LNDG. NO FURTHER ENG FLUCTUATIONS OCCURRED. UNEVENTFUL LNDG AND TAXI-IN.