DTC P1441: EVAP System Flow During Non-Purge: Description
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This Diagnostic Trouble Code (DTC) tests for undesired intake manifold vacuum flow to the Evaporative (EVAP) emission system. The Powertrain Control Module (PCM) seals the EVAP system by commanding the EVAP purge valve OFF (closed) and the EVAP vent valve ON (closed). The PCM monitors the Fuel Tank Pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP system. If the vacuum in the EVAP system is more than a calibrated value within a calibrated time, DTC P1441 will set.