Evaporative Emission Control Canister: Testing and Inspection

1. Connect tachometer, then start engine and run until it reach normal operating temperature.
2. Remove fuel filler cap.
3. Remove canister purge air hose from frame and connect it to suitable vacuum gauge.
4. Raise engine speed to 3500 RPM. Vacuum should appear on gauge within one minute. If so, remove gauge and proceed to step 14.
5. If vacuum does not appear within one minute, disconnect vacuum gauge and install fuel filler cap.
6. Remove charcoal canister and inspect for damage or defects, replacing as necessary.
7. Stop engine, then disconnect hose from canister "PCV" fitting.
8. Connect suitable hand vacuum pump to canister "PURGE" fitting and draw vacuum. Vacuum should remain steady.
9. If vacuum drops, replace canister and repeat test.
10. Start engine, then connect hose to canister "PCV" fitting. "PURGE" side vacuum should drop to zero. If not, replace canister and repeat test.
11. Connect suitable hand vacuum pump to canister "PCV" fitting and draw vacuum. Vacuum should remain steady.
12. If vacuum drops, replace canister and repeat test.
13. If vacuum remains steady, disconnect vacuum pump and test operation of thermovalve.
14. Connect vacuum pump to "TANK" fitting and draw vacuum. There should be no vacuum.
15. If there is vacuum, replace canister and repeat test.
16. If there is no vacuum, install fuel filler cap and canister.