Evaporative System Monitoring

The Evaporative Emission Control Monitoring System monitors fuel vapor generation, evacuation, and a leakage check step. At first, the OBD-II system checks if vapor generation due to fuel temperature is small enough to start monitoring. Then it evacuates the evaporative system by means of PCSV with ramp in order to maintain a certain vacuum level. The final step is to check if there is vacuum loss by any leakage of the system.