Air leak solenoid valve (Honda Accord 3)

During normal engine operation, a small amount of air is bleed into the primary jets of the carburetors to regulate the mixture and improve fuel atomization. During cranking or full throttle operation, the bleed valve is closed to provide a slightly rich air/fuel mixture. On the Prelude, this valve is located inside the air cleaner between the carburetors. The ECU controls this valve based on parameters such as vehicle speed, ignition key position, transmission or clutch switch position, vacuum switch position, coolant and intake air temperature, and MAP sensor readings.

Checking functionality

1. Remove the air filter and connect a hand pump to the valve. Pump out air while the engine is idling. The engine must be cold. The valve must hold a vacuum of 102 mm Hg. If the valve holds the specified vacuum, warm up the engine.

2. When the engine warms up to operating temperature and the incoming air temperature is at least 70°C (measured on the sensor in the air intake manifold), the valve should stop holding vacuum. If the valve holds vacuum under these conditions, and there is no voltage on the green conductor of the solenoid, then the solenoid or the bleed valve inside the solenoid is faulty.

3. If there is voltage on the solenoid at idle, then the ECU device is faulty.

(The text can be found on the website: «HondaBook»)