Test Group VBM2.8VJGKFK

Evaporative System Monitoring General Description -  The evaporative system monitoring permits the detection of leaks in the evaporative emission control system with a diameter of 1 mm and up. See Fig 1.

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, pressure increase is measured by a tank pressure sensor. If vacuum increases above a defined threshold a leak is detected. As part of the vacuum check, purge flow is verified. For vapor generation test and EVAP system diagnosis, see Fig 2-Fig 5 .

Fig 1: EVAP System - Monitoring Structure (Test Group VBM2.8VJGKFK & VBM2.8VJGKEK)

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Fig 2: EVAP System - Test For Vapor Generation (Test Group VBM2.8VJGKFK & VBM2.8VJGKEK)

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Fig 3: EVAP System - System Diagnosis Flow Chart (Test Group VBM2.8VJGKFK & VBM2.8VJGKEK)

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Fig 4: Fuel Tank Leak Check Pressure Diagram (Test Group VBM2.8VJGKFK & VBM2.8VJGKEK)

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Fig 5: OBD-II Evaporative System Diagram (Test Group VBM2.8VJGKFK & VBM2.8VJGKEK)

Courtesy of BMW OF NORTH AMERICA, INC.