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Evaporative Check Valve: Description and Operation

ENGINE CONTROL COMPONENTS

Evaporative Emission (EVAP) Ejector Venturi Assembly
The EVAP ejector venturi assembly is used on turbocharged engines to create a vacuum in the EVAP purge line from the canister purge valve to the intake air system. During boost conditions, boost pressure flows through venturi inside the EVAP ejector venturi assembly creating a vacuum in the EVAP purge line to the intake air inlet to the turbocharger. When the second EVAP canister purge check valve is open, the purge vapor is drawn through the EVAP ejector venturi assembly into the intake air tube, through the turbocharger and charge air cooler, to the intake manifold.