20. EVAPORATIVE EMISSION CONTROL SYSTEM Downtown 300i ABS
EVAPORATIVE EMISSION CONTROL SYSTEM FUNCTION
FOREWORD:
The Evaporative Emission Control System is abbreviated to E.E.C. System. This device collects
the fuel vapor from the fuel tank and then the fuel vapor is drawn into the engine for re-burning to
avoid air pollution caused by the fuel vapor diffused into the air.
FUNCTION
Item Purpose Function
The charcoal canister absorbs vaporized HC
Control vaporized HC from from the fuel tank. When the engine is
Purge Control Valve fuel tank not to diffuse into running and the purge control valve is open,
the air. the fuel vapor in the charcoal canister is
drawn into the engine for re-burning.
Absorb and store the The vaporized HC is absorbed in the charcoal
Charcoal Canister vaporized HC from the fuel canister and the specified volume of HC in
tank and carburetor. the emission should not exceed 2g.
Through the P.C.V. system, the blow-by gas
Completely recover the HC from the crankcase is separated into fuel
P.C.V. System from blow-by gas in the vapor and fuel and then drawn into the
crankcase for re-burning. cylinder for re-burning.
TROUBLESHOOTING
Engine loses power or runs erratic at idle speed
1. Clogged P.C.V. system
2. Clogged air cleaner
3. Faulty purge control valve
4. Loose or broken E.E.C. system tubes
Engine idles or accelerates roughly
1. Faulty fuel cut-off valve
2. Faulty purge control valve
3. Clogged or faulty charcoal canister
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4.7 / 5