What was found
DURING L ENG START WHEN STARTER MOVED TO "GND" DUCT PRESS DROPPED TO ALMOST NOTHING, N2 NEVER SPOOLED UP TO MORE THAN 15%. DUCT PRESS WAS 30 PSI PRIOR TO THIS.(<P>SWAPPED ECU WITH KNOWN GOOD PART, OPS CHECK BAD. RETURNED AIRCRAFT TO ORIGINAL CONFIG. TRANSFERRED TO MDDR #128556, CAT 'C', DUE 29MAY20. MCC NOTIFIED. PLACARDS INSTALLED. DDG 49-11-01-01. YK @ 13:46. APU PNEUMATICS INOP. </P><P>LP 1189517: REMOVED AND REPLACED BOTH ENGINE STARTERS (STARTER OFF PART: PN <SPAN>3505448-5, SN </SPAN><SPAN>AEX02712C</SPAN><SPAN>) AND BOTH ENGINE START VALVES (OFF PARTS: PN </SPAN><SPAN>3291172-3, SN 410C; PN 3291172-3, SN 1683C</SPAN><SPAN>) IAW B767 AMM REF 80-11-01 AND 80-11-02. BOTH ENGINE STARTERS AND APU OPS CHECKED GOOD IAW AMM 71-00-00. THIS CLEARS MDDR 128556.</SPAN></P>)