AEM 2011-2013 Volkswagen Jetta 2.5L L5 - Cold Air Intake SystemAEM Cold Air Intake Systems are designed to produce horsepower and torque gains. They replace the restrictive factory airbox and air filter to give you better performance and better engine sound. AEM cold air intakes relocate the air filter outside the engine compartment so cooler air can be fed into your engine. Cooler air carries more oxygen, which translates into a more intense explosion in the combustion chamber for more horsepower and torque. AEM