Charcoal Canister Check
Attach a hose to the fuel vapor port (from fuel tank) of the canister and attempt to blow through it. Air should pass into canister. If not, replace the canister.
Attach a hose to the EEC port (from engine mounted solenoid) of the canister, and attempt to blow through it. Air should not pass into the canister. If air passes, replace canister. Reconnect all hoses.