Evaporative Emission System Uses 4 Basic Components Buick Riviera VIII

1. Activated carbon canister (may be sealed or open at top or bottom for fresh air intake).
2. Tank pressure control valve (mounted internally or externally to fuel tank).
3. PCM-controlled canister purge control solenoid (mounted in-line or on canister).
4. Canister purge control valve (mounted in-line or on canister).

See appropriate EMISSION APPLICATIONS article for specific component application. For vacuum hose routing, see VACUUM DIAGRAMS article.