Charcoal Canister: Notes

Check for clogged filter and/or stuck check valve by blowing low pressure compressed air into canister tank port. Check that air flows freely out of other canister ports.
On fuel injected Pickup and 4Runner, blow air into canister purge port and check that air does not flow out of any other port.
On carbureted Pickup and 4Runner, blow air into the purge port and check that air flows freely through other ports. Replace canister if it does not operate as outlined.