What was found
FLT 252 - MEX-GDL - AIRCRAFT RETURNED TO GATE DUE TO ACCELERATION FAILURE OF LEFT ENGINE. THE ACCELERATION CHAMBER WAS REVISED AND IT WAS PERFORMED A TRIM IAW MM 73-20-03 AND 73-11-00, TESTS OK. THE FCU OF LEFT ENGINE WAS REPLACED, TRIM WAS PERFORMED, TESTS OK, IAW MM 73-12-02, 71-00-01, 72-00-00. (M)