| 摘要 |
<p>When an air pump evaluation method is employed, an ECU (15) closes off a conduit (5) from the atmosphere by closing a canister vent solenoid valve (11), and drives an air pump (12) to pressurize the conduit (5) to a target pressure, after which the air pump (12) is stopped and a check valve (13) is closed, placing the conduit (5) in an airtight state, and the airtightness is evaluated on the basis of pressure variation measured by a pressure gauge (6). When the conditions are such that it is desirable to avoid driving the air pump (12), an EONV evaluation method is employed and the airtightness is evaluated on the basis of natural pressure variation due to temperature changes in the conduit (5) when the canister vent solenoid valve (11) and the check valve (13) are closed.</p> |
