Examination (engine D15Z7, D16Y6, V16A4, V16A5, V16A6)
1. Remove the fuel tank cap.
2. Start the engine and leave it idling.
3. Disconnect the vacuum hose from the EVAP purge control diaphragm valve and attach a vacuum gauge to the hose.
If there is no vacuum, check for blockages, cracks, or disconnections in the vacuum hose, or for a clogged vacuum connection.
4. Disconnect the vacuum pressure gauge and connect the hose.
5. Attach a vacuum gauge to the EVAP accumulator purge hose.
6. Increase engine speed to 3500 rpm. A vacuum should appear on the pressure gauge within 1 minute.
If vacuum appears on the pressure gauge after 1 minute, remove the pressure gauge, the test is completed. If there is no vacuum, disconnect the vacuum gauge and install the fuel tank cap.
7. Remove the fuel vapor accumulator tank (EVAP) and check for any signs of damage or defect.
If damaged, replace the barrel.
8. Stop the engine. Disconnect the vacuum hose from the EVAP diaphragm valve. Attach the vacuum pump to the lower hose as shown and create a vacuum.
The vacuum must be stable (unchanged).
If the vacuum drops, replace the EVAP control reservoir and check again.
9. Start the engine. Connect the upper vacuum hose to the EVAP diaphragm valve. Underpressure (lower vacuum hose side) should drop to 0.
If the vacuum does not drop to 0, replace the EVAP reservoir and check again.
Checking the two-function valve (EVAP) fuel vapor accumulator.
1. Remove the fuel tank cap.
2. Remove the steam line from the dual function valve on the fuel tank and attach the T-piece from the vacuum gauge and vacuum pump as indicated.
3. Slowly create a vacuum while watching the pressure gauge.
The vacuum should stabilize momentarily at 0.7-2.0 kPa.
If the vacuum has stabilized (valve opens) below 0.7 kPa or above 2.0 kPa, install a new valve or check again.
4. Switch the hose to the pump discharge outlet and switch the vacuum gauge hose from the pressure side as indicated.
5. Slowly increase the pressure in the steam line while watching the pressure gauge.
The pressure should stabilize at 1.3-4.7 kPa. If the pressure stabilizes momentarily (valve opens) at 1.3-4.7 kPa, the valve is ok. If the pressure stabilizes below 1.3 kPa or above 4.7 kPa, install a new valve and check again.