What was found
AIRCRAFT HAD DIFFICULTY CLIMBING THRU FL 31000. RT ENG FUEL FLOW AT .7 (700 LBS/HR), N1, EGT AND N2 WERE SIGNIFICANTLY BELOW LT ENG. CONDUCTED QRH ENGINE INFLIGHT. START CHECKLIST AND RT ENG STARTED WITH NO PROBLEMS. ENGINE OPERATED WITHIN ALL LIMITATIONS AND PARAMETERS. R & R ECU IAW AMM 73-21-15, NO FAULTS IAW 73-21-27-01, R & R THE NR 2 HMU AND TEST GOOD IAW AMM 73-21-14-401.