As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT ENGINE WAS SURGING UP TO 9% N1 AT IDLE FROM TOP OF DECENT ALL THE WAY TO LANDING.(<P>PERFORMED FIM 71-05 FT 848. OPS CHECK NORMAL, NO MSG'S. PERFORMED ENGINE RUN OF LEFT ENGINE AT IDLE AND 28% N1, NO FLUX IAW 71-00-00. OPS CHECK NORMAL.