Primary HO2S Replacement

Special Tools Required 

1. O2 sensor wrench, Snap-on YA8875, SP Tools 93750, or equivalent, commercially available

1. Disconnect the primary HO2S 4P connector (A), then remove the primary HO2S (B).
   Fig 1: Disconnecting The Primary HO2S 4P Connector

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
2. Install the primary HO2S in the reverse order of removal.