Examination (except for engines D14A3, D14A4)
1. Remove the fuel tank cap.
2. Start the engine and let it idle.
3. Disconnect the vacuum hose from the evaporative emission control valve and connect the vacuum gauge to the hose.
If there is no vacuum, check the vacuum hose and fitting for blockages, leaks, or damage.
4. Disconnect the vacuum sensor and reconnect the hose.
5. Connect the vacuum sensor to the air hose of the ventilation system.
6. Increase engine speed to 3500.
The gauge should show a vacuum within one minute.
If a vacuum appears, remove the sensor - the test is complete.
If there is no vacuum, disconnect the vacuum sensor and replace the tank cap.
7. Remove the EVAP reserve tank and inspect for signs of defects or damage.
8. Stop the engine. Disconnect the upper hose from the diaphragm purge control valve. Attach a vacuum pump to the lower hose and apply vacuum.
The vacuum must be stable.
Vacuum is dropping, replace EVAP reserve tank and recheck.
9. Start the engine, connect the upper vacuum hose to its place. Vacuum (in the lower hose) should drop to zero.
* If the vacuum does not drop to zero, replace the EVAP reserve tank and recheck.
Checking the Dual-Way EVAP Valve
1. Remove the fuel tank cap.
2. Disconnect the vapor discharge hose from the two-way valve and connect it to the pressure/vacuum sensor and vacuum pump via a T-piece as shown in the figure.
3. Pump the vacuum slowly and continuously, while monitoring the gauge. The vacuum should stabilize for short intervals at a value of 0.7-2.0 kPa (5-15 mm R.S.).
If the vacuum stabilizes (the valve opens) at a value below 0.7 kPa or above 2.0 kPa, replace the valve and recheck.
4. Switch the hose to the vacuum pump discharge port and the pressure input from the sensor to the T-piece as shown in the figure.
5. Slowly pump up the pressure, watching the gauge. The pressure should stabilize at a value of 1.3-47 kPa (10-35 mm R.S.).
If the pressure stabilizes briefly (the valve opens) within the specified limits, the valve is OK.
If the pressure stabilizes below or above the specified zone, replace the valve and recheck.