Fuel Injected Models: Canister
When coolant temperature is greater than specification, purge thermovalve on Prelude directs manifold vacuum to purge control valve on top of canister. This allows ported vacuum to draw vapors from canister into throttle body port. When coolant temperature is less than this temperature, no vacuum is applied to purge control valve.
When coolant temperature is greater than specification on Civic and Accord, ECU energizes purge cut-off solenoid valve, allowing manifold vacuum to activate purge control diaphragm valve on top of canister. This allows ported vacuum to draw vapors from charcoal canister. See PURGE OPERATING TEMPERATURE table.