Unfreezing Chevy PCV

Oct. 29, 2024
This bulletin applies to 2020-2023 Chevy Blazer vehicles equipped with a 2.0L engine.

This bulletin applies to 2020-2023 Chevy Blazer vehicles equipped with a 2.0L engine. If you encounter a vehicle setting DTC P04FB in temperatures below freezing that has failed current or history, complete the published SI diagnostics for the DTC.

If unable to establish a root cause, remove the PCV/crankcase pressure sensor and hose assembly and inspect the frozen moisture/condensation in the sensor and hose assembly. If frozen moisture is found, allow the assembly to thaw out and drain completely.

Use a combination of light compressed air and a shop towel to remove any residual moisture. There is no need to replace the sensor and hose.

About the Author

Motor Age Staff

Motor Age has been publishing technical content for professional automotive technicians since 1899. Our writers have decades of experience and scores of ASE certifications, and they continue to teach new generations of technicians via classrooms all around the globe, as well as through the books and training manuals they've authored. 

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