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Increasing population and a rising necessity for mobility and transportation require a growing environment protection. In the USA and in Europe legislative concluded new emission limits to reduce cold start emissions for passenger cars. A useful method to reduce HC and CO during the cold start of combustion engines is secondary air injection. Secondary air injection feeds fresh air into the exhaust system during cold start and achieves an oxidation of unburned HC and CO. This exothermal oxidation elevates the exhaust gas temperature and decreases light-off time of the catalyst. A large portion of the emissions in the FTP 75 cycle is produced during the first seconds of the cold start. This requires a fast rising secondary air mass flow during the cold start of the engine. Electrically driven secondary air pumps achieve this requirement with a high cut-in current. Mann+Hummel developed the so called secondary air charger with a very short response time.

Increasing population and a rising necessity for mobility and transportation require a growing environment protection. In the USA and in Europe legislative concluded new emission limits to reduce cold start emissions for passenger cars. An effective method to reduce HC and CO during the cold start of combustion engines is secondary air injection. Secondary air injection mixes fresh air into the exhaust gas during cold start and achieves an oxidation of HC and CO. This exothermal oxidation elevates the exhaust gas temperature and decreases light-off time of the catalyst. A new compact secondary air injection system for integration in the intake manifold, the so called Secondary Air Charger was developed. In principle the secondary air charger works as a turbocharger, driven by the pressure drop at the throttle valve. This system was analyzed on test rigs, engine test bench and passenger car, successfully.

The design principles for air intake systems (consisting of an air filter, intake manifold, resonators and air hoses) of passenger cars and the components themselves have changed in the past due to changes in customer requirements and legislation. The intake system components, for the most part, are still developed as single parts, not as a common intake system. The interactions within the complete system, concerning gas dynamics, acoustics and other aspects, are often only considered in a late development stage. To fulfill future demands, changes in the intake system development process and changes in intake system technology are necessary. This will be shown by examples.