As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON TAKE OFF AFTER SPOOL UP OF ENGINES. RIGHT ENGINE WAS SLOW TO SPOOL ANY FATHER. IT DID NOT MATCH LEFT ENGINE WHICH APPEARED TO SPOOL NORMALLY. APORTED TAKE-OFF AND TAXIED BACK TO THE GATE. MAINTENANCE GROUND RAN THE NR 1 AND NR 2 ENGINE FOR POWER ASSURANCE RUN TEST NR 8. OPERATIONAL TEST GOOD IAW B737 MM 71-00-00