Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Emission Control Systems: Description and Operation


The emission control systems are used to reduce harmful gases (Hydrocarbons (HC), Carbon Monoxide (CO), and Oxides of Nitrogen (NOx)) in accordance with federal and state regulations.

The Three Way Catalytic Converter converts HC, CO, and NOx into Carbon Dioxide (CO2), Water Vapor (H2O), and Nitrogen (N2).

The Evaporative Emissions System prevents HC vapors from escaping into the atmosphere.

The Fillpipe Restrictor prevents leaded fuel from contaminating the Three Way Catalytic Converter.

The Positive Crankcase Ventilation helps in the reduction of HC and CO.