As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 1303 - EN ROUTE DFW/MEX, LEFT ENGINE OIL QUANTITY SHOWED STEADY DECREASE POSSIBLY INDICATING HIGH OIL CONSUMPTION ON NR 1 ENGINE. EMERGENCY WAS DECLARED AND AIRCRAFT LANDED IAH WITHOUT INCIDENT. REPLACED NR 1 ENGINE OIL INDICATOR. SYSTEM GROUND CHECKED, NORMAL OPERATION. (X)