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Home >> Chevrolet >> 2005 >> Optra5 Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 1.8L (L79) - Introduction And Mechanical Repairs >> Description and Operation >> Crankcase Ventilation System Description >> Notes
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Crankcase Ventilation System Description: Notes

The compressed combustion gas which escapes past the piston rings into the crankcase is known as blow-by gas. Blow-by gas contains large amounts of CO and HC. The positive crankcase ventilation (PCV) system prevents the blow-by gas from being emitted into the atmosphere. The PCV system routes the crankcase blow-by gas back into the intake system where the blow-by gas becomes part of the combustion process. The PCV system consists of the following components: