2017 2.7l F150 Code P1446C
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P144C - EVAP System Purge Flow Performance During Boost
Description:The EVAP check valve test is performed during minimal boost conditions, once per drive cycle, when entry conditions are met. This DTC sets when the fuel tank pressure exceeds a calibrated amount within a specified amount of time during the test (single path check valve), or when the fuel tank vacuum is less than a calibrated amount within a specified amount of time or when the fuel tank pressure exceeds a calibrated amount within a specified amount of time during the test (dual path check valve).
Possible Causes:
Description:The EVAP check valve test is performed during minimal boost conditions, once per drive cycle, when entry conditions are met. This DTC sets when the fuel tank pressure exceeds a calibrated amount within a specified amount of time during the test (single path check valve), or when the fuel tank vacuum is less than a calibrated amount within a specified amount of time or when the fuel tank pressure exceeds a calibrated amount within a specified amount of time during the test (dual path check valve).
Possible Causes:
- Restricted EVAP ejector connections at the intake air system
- Stuck open EVAP check valve
- Stuck closed EVAP check valve
- Damaged EVAP ejector
- Damaged EVAP check valve
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The Powertrain Control Module (PCM) tests the Evaporative Emission (EVAP) canister purge check valve for a stuck open condition. The EVAP canister purge check valve test is performed during minimal boost conditions, once per drive cycle, when entry conditions are met.