As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI AFT FA REPORTED A BURNING RUBBER OR BURNT FUEL SMELL . PASSENGERS IN LAST THREE ROWS WERE CONCERNED. SHE REPORTED AFTER BLOCK RETURN THAT THERE HAD BEEN A THUMP SOUND ON BACK RIGHT. CLOSE TO AFT COFFEE MAKERS AND THEN SMELL STARTED. SMELL DISSIPATED IN A FEW MINUTES WITH NO CREW ACTION.