What was found
DURING CLIMB AT ABOUT 17000FT MANIFOLD FAILURE NR 3 ALERT AND 18500FT MANIFOLD FAILURE NR 1 ALERT. FUEL DUMPED TO MLW AND ACFT RTB (MIA) WITH NO INCIDENT. REMOVED AND REPLACED PSC NR 1 AND NR 2 IAW MD11 AMM 36-10-02. RTS ON PSC NR 1 & NR 2 PASSED IAW MD11 AMM 36-10-02. PERFORMED PNEUMATIC OP CHECK AT MAX POWER IAW MD11 AMM 36-00-03 AND NO DEFECTS NOTED. PERFORMED PNEUMATIC SYSTEM PRESSURE DECAY CHECK WITH ENGINES RUNNING IAW MD11 AMM 36-00-02 AND NO DEFECTS NOTED. ENVIRONMENTAL SYSTEM CONTROLLER AUTO MODE INOP - OK IN MANUAL. TRANSFERRED TO DMI 8368 IAW MEL 21-08-1-1 CAT C EXP 02/14/13. MAINTENANCE PROCEDURES ACCOMPLISHED.