Evaporative Emission Control Canister: Testing and Inspection

Vapor Canister:

^ Apply a short length of hose to the lower tube ("PCV") of purge valve and blow into it. Very little air should pass into canister if any at all. If the canister has a constant purge orifice a small amount of air may go into canister. If air passes into canister, replace canister. If air does not pass into canister proceed to next step.

Use a hand vacuum pump and apply 15" Hg of vacuum to the tube labeled "CONTROL VAC" on the purge valve diaphragm cover. The diaphragm should hold vacuum for at least 20 seconds. If it does not replace the canister. If it does hold vacuum proceed to next step.

With vacuum still applied to the control vacuum tube, blow into tube labeled "PCV." If air flow into the canister increased, purge valve is ok. If air flow does not pass into the canister, purge valve is bad and canister must be replaced.