An induction system in an engine is provided. The air induction system includes an induction conduit including an air flow passage in fluidic communication at least one combustion chamber in the engine and a passive-adsorption hydrocarbon trap positioned within the induction conduit, a portion of the passive-adsorption hydrocarbon trap defining a boundary of the air flow passage, the passive-adsorption hydrocarbon trap including a breathable layer coupled to a substrate layer coupled to the induction conduit, a hydrocarbon adsorption layer interposing the breathable layer and the substrate layer.