Feedback Carburetor System: Description

All Honda models use a feedback carburetor system (except Civic 1300). The feedback carburetor system maintains the proper air/fuel ratio during engine operation. Air control valves are used to allow additional air into the intake manifold to adjust a temporarily rich mixture condition. The system is made up of the X-subsystem and M-subsystem.

The X-subsystem consists of an air control valve B, frequency solenoid B, constant vacuum valve, check valve B, surge tanks A and B, and the control unit. The M-subsystem consists of a check valve A, air control valve A, frequency solenoid valve A and the control unit.

The surge tank A is used as a reservoir. The surge tank B is used to dampen vacuum pulses to the air control B.