Purge flow monitor

If EVAP system pressure change is less than 7.5 mmHg (1 kPa) when the engine is running and the purge VSV is turned ON (closed), the ECM determines that the purge flow is insufficient.

Fig 1: EVAP Purge Flow Diagram

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Fig 2: Purge Flow Monitor Components Operation Chart

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Fig 3: Pump Module On/Off Diagram

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Fig 4: Pressure Sensor Output Voltage Graph

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Fig 5: Soak Timer Circuit Diagram

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