NC Training Guide - Miata.net

01 ENGINEEmission SystemEvaporative Emission (EVAP) System Leak Detection PumpConstruction/OperationStructure• Orifi ce— Has a 0.5 mm (0.02 in)hole• Pump— Force-feeds air to theorifi ce and the EVAP lines• Heater— Removes moisture insidethe pump• Change over valve— Operated by a solenoidvalve to switch air passagesOperationEvaporative system normal operation• While driving, air passes through thechange over valve through the charcoalcanister then to fuel tank to compensatefor the fuel being used.• The passage between the charcoalcanister and the air fi lter is connected.During fuel expansion or when fi llingthe fuel tank, fuel vapor passes throughcharcoal canister through changeovervalve then to atmosphere.SG-96Mazda Technical TrainingMX-5 Miata New Model Training