As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKE OFF, RIGHT FAN RPM TAPE JITTERED THEN WENT TO MAX INDICATION. REDUCED RIGHT ENGINE POWER, CHECKED OTHER PARAMETERS, NORMAL. TROUBLESHOT AND DETERMINED TO BE BAD GAUGE. ACQUIRED LOANER FROM MFG AND INSTALLED. OPS CHECKED GOOD.