DTC code

P0446: Evaporative Emission EVAP Vent System Performance

Vehicle-specific published guides for this diagnostic trouble code.

P0446/Engine diagnostics

Evaporative Emission EVAP Vent System Performance

P0446 may mean the EVAP system is not venting the fuel tank normally, so the fuel tank pressure reading can move outside the expected pattern during the EVAP monitor.

Article vehicle: 2014-2018 Gmc Sierra 1500 5.3 gas

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P0446/Engine diagnostics

EVAP vent system performance

P0446 may mean the ECM is seeing EVAP tank pressure behavior that does not match the expected vent system response.

Article vehicle: 2019-2025 Chevrolet Silverado 1500 5.3 gas

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