As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD INFLIGHT T1877/18APR AFTER TAKE OFF LEFT HAND ENGINE COMPRESSOR STALLED. THROTTLE RETARDED AND INDICATIONS NORMAL. RETURNED TO ORD AND LANDED WITHOUT INCIDENT. METAL DEBRIS FOUND IN LEFT HAND ENGINE EXHAUST. REPLACED LEFT HAND ENGINE ON 19 APR 2007 AT ORD. SYSTEM GROUND CHECKED NORMAL OPERATION. (CLOSED)