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Engine out (feedgas) emissions control during cold start operations has been a major technical challenge since mandated LEV/ULEV/SULEV/PZEV regulation compliance. Cold start emissions contribute to more than 85% of total emissions in a FTP test. Unburned Hydrocarbons are mostly generated during cold starts due to a rich Air/fuel ratio strategy. Cold intake and cylinder wall surfaces do not provide a quick vaporization bed for the rich fuel, therefore un-vaporized and unburned fuel result in excessive tailpipe emissions. Utilizing fuel vapor during cold starts reduces the Hydrocarbon (HC) emissions level and minimizes the transient fuel effect process. A vapor management system must function to control the Air-to-fuel ratio of the intake charge during “cold-starts”, idle, and drive-away, or until catalyst lights off to a desired level.