This diagnosis detects leaks in the Evaporative Emission System (EVAP) purge line using engine intake manifold vacuum. If pressure does not increase, the Engine Control Module (PCM) will check for leaks in the line between the fuel tank and the PCSV(Purge Control Solenoid Valve) under the following vacuum test condition. The vacuum cut valve bypass valve is opened to clear the line between the fuel tank and the PCSV(Purge Control Solenoid Valve). The CCV(Canister Close Valve) will then be closed to shut the EVAP purge line off. The PCSV(Purge Control Solenoid Valve) is opened to depressurize the EVAP purge line using intake manifold vacuum. After this depressurization is implemented, the PCSV(Purge Control Solenoid Valve) will be closed.