PCV - Overview (2016 2017 2018 2019 2020 2021 2022)
Some of the unburned gases in the combustion chamber will leak through the gap between the pistons and cylinders into the crankcase. The blow-by gases that include the unburned gases are returned through the positive crankcase ventilation (PCV) valve and are burned. This prevents the blow-by gases from being released to the atmosphere.