Evaporative Emission System: Notes

All vehicles use carbon canister storage for evaporative fuel control. Evaporative emission control system stores gasoline fumes from fuel tank in a carbon canister. After engine is running, fumes are drawn into engine for burning during combustion process.

The basic components used in the evaporative emission system are an activated carbon canister (all models, open at top or bottom for fresh air intake), vacuum operated canister control valve (some Federal models), or purge control solenoid (all other models). For specific component application and vacuum hose routing, see VACUUM DIAGRAMS - TRUCKS article.