Economizer valve (Honda Accord 3)

There is a valve at the bottom of the carburetor, the opening of which supplies additional fuel to the main jet channel. The valve is actuated by vacuum supplied through a two-way electromagnetic valve, which, in turn, is activated by the ECU during periods of sharp acceleration. The ECU opens the electromagnetic valve taking into account the readings of the MAP sensor and the temperature sensor. If the electromagnetic valve is open (off state) in idle mode, the engine will operate with an over-rich mixture and produce an excessive amount of exhaust gases.

Checking functionality

1. Start the engine and let it warm up to operating temperature. Disconnect hose #14 from the vacuum manifold and connect a vacuum gauge. There should be a vacuum there, indicating the on state of the two-way valve, in which the vacuum path to the economizer valve is blocked.

2. If there is no vacuum, then the unit should be checked for leaks. It is also necessary to make sure that there are 12 volts between the contacts of the green/yellow and black wires of the solenoid valve when the engine is idling.

3. If there is no voltage at the solenoid valve, check the green/yellow wiring that connects the valve to the ECU. If there are no open or short circuits in the wiring, then the ECU is either faulty or not receiving correct data from the measuring sensors.