Evaporative Emissions (Evap) Control System Structure; Evaporative Emissions (Evap) Control System Operation; Purge Solenoid Valve Function - Mazda RX-8 2004 Service Highlights

EVAPORATIVE EMISSIONS (EVAP) CONTROL SYSTEM STRUCTURE

• Consists of a purge solenoid valve, charcoal canister, catch tank, evaporative chamber, rollover valves, fuel
shut-off valve, EVAP system leak detection pump, air filter, and fuel-filler cap.
CHARCOAL CANISTER
AIR FILTER
EVAP SYSTEM LEAK
DETECTION PUMP
EVAPORATIVE
CHAMBER
FUEL FILLER CAP
End Of Sie

EVAPORATIVE EMISSIONS (EVAP) CONTROL SYSTEM OPERATION

• When the engine is stopped, evaporative gas in the fuel tank flows from the fuel tank as pressure rises, and is
absorbed by the charcoal canister. Additionally, liquefied evaporative gas is stored in the catch tank.
• When the engine is running, evaporative gas absorbed by the charcoal canister together with air drawn from
the atmospheric air port in the charcoal canister passes through the purge solenoid valve and is then inducted
into the engine in an amount appropriate to engine condition.
• If negative pressure in the fuel tank rises, air is drawn from the charcoal canister atmospheric air port via the
rollover valves. If the atmospheric air port in the charcoal canister becomes clogged, this malfunction causes
negative pressure in the fuel tank to rise, applying a load to the fuel tank, and the negative pressure valve in the
fuel-filler cap opens to draw air into the fuel tank.
End Of Sie

PURGE SOLENOID VALVE FUNCTION

• Adjusts the amount of evaporative gas drawn into the intake-air system.
End Of Sie
01–16–8
EMISSION SYSTEM
FUEL SHUT-OFF VALVE
ROLLOVER VALVE
CATCH TANK
PURGE SOLENOID VALVE
CHU011601074S02
CHU0116S011
CHU011601074S03
CHU011618740S03