Primary idle mixture cut-off solenoid valve (Honda Accord 3)

The purpose of this valve, installed in each of the carburetors, is to shut off the fuel supply to the idle circuit. They are open when the ignition is on and closed when decelerating or when the ignition is off. The ECU controls these valves, taking into account such parameters as the position of the ignition key, the position of the transmission or clutch, the position of the vacuum switch, and the readings of the MAP sensor. It is necessary to check the correct closing of these valves with the engine running and the clutch engaged, when the drive wheels are rotating.

Checking functionality

1. Turn on the ignition and disconnect the black/yellow wire contact from each valve in turn. When the contact is broken, you can hear the valve clicking. If any of the valves remain open, the engine will probably continue to run even with the ignition off.



2. Before checking the correct closing of the valves during braking of the car, it is necessary to raise and firmly support the car on stands so that the drive wheels can rotate freely. Disconnect the wire from one of the valves and connect a voltmeter between the black/yellow wire and the ground.

3. Start the engine and let it warm up to operating temperature. With the rear wheels locked, shift the transmission into second gear and bring the engine speed to 2000 rpm. When you release the accelerator pedal, the voltage on the disconnected valve should instantly drop to zero.