111 589 00 91 00 Connector - WS01.00-P-0018B

FG 01/Set B 

ENGINE 104, 111, 112, 113, 119, 120, 137, 166, 266, 271, 272, 273 

Use: 

Connector for air pressure via glow plug bore to pressure build-up in combustion chamber

Fig 1: Identifying Connector (111 589 00 91 00)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.