As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB OUT, N1 FOR THE LT ENGINE KEPT GOING DOWN ABOUT 10% AND LEFT ENGINE NOISE WAS GOING DOWN AS WELL & PLANE WAS YAWING TO THE LEFT HAPPENED MULTIPLE TIMES, NO OTHER ABNORMAL INDICATION ON ITT OR N2. DIVERTED. PERFORMED ENGINE RUNS IAW AMM 76-00-00, WITH BOTH SPEED SWITCHES ON AND OFF COULD NOT DUPLICATE. PERFORMED OPS CHECK OF APR IAW AMM 76-13-00, OPS CHECKED PASSED.