As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM, LEFT ENGINE SURGING EPR .01 TO .02 N1 .1 TO .3 TENTHS IN CRUISE FLT LEVEL 350. FOLLOWED PROCEDURES IN FIM 73-21-00 TESTED PIMU NO FAULTS NOTED. CHECKED FUEL FILTER AND EGT HARNESS NO FAULTS NOTED NOTIFIED MOC . OK FOR SERVICE.