ECT Sensor 1 Replacement

Drain the engine coolant (see COOLANT REPLACEMENT ).
Remove the intake manifold cover (see step 1 in REMOVAL ).
Disconnect the ECT sensor 1 2P connector (A).

Fig 1: Disconnecting ECT Sensor 1 2P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove ECT sensor 1 (B).
Install the sensor in the reverse order of removal with a new O-ring (C), then refill the radiator with engine coolant (see COOLANT REPLACEMENT ), and bleed air from the cooling system with the heater valve open.