As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER ENGINES STARTED, AN ACRID ODOR SEEMED TO ORIGINATE FROM THE LT PACK. WE ALSO HEARD A WHINNING NOISE AS THE THRUST LEVERS WERE ADVANCED. BOTH THE SMELL AND THE WHINE DID NOT RECUR WITH THE LT PACK OFF. INWORK. TROUBLESHOT AND FOUND ACM NOT TURNING WHEN PACK IS ON. R & R ACM IN REF TO AMM 21-51-03-4. OPS AND LEAKS CHECK GOOD. ACFT OK FOR SERVICE. PREMATURE REMOVAL/INSTALLATION.