Evaporative Purge System Monitoring
GENERAL DESCRIPTIONEVAP. FAMILY XBMXE0156E36
The evaporative system monitoring permits the detection of leaks in the evaporative emission control system with a diameter of 1 mm and up.
The evaporative emission control system is hermetically sealed off from the atmosphere by means of a shut-off valve at the charcoal canister. When the purge valve opens, the engine generates a vacuum in the tank. After closing the purge valve the pressure increase is measured by a tank pressure sensor. If the vacuum increases above a defined threshold a leak is detected.
As part of the vacuum check the purge flow is verified.
MONITORING STRUCTURE
Test for vapor generation
Evaporative system diagnosis
OBD-II Evaporative System
leak check - fuel tank pressure diagram
OBD-II Evaporative System