The intake tract includes all components of an internal combustion engine that carry combustion air and are located in front of the combustion chamber . It usually consists of an intake opening, an air filter and an intake manifold (with preheating if necessary). The air filter can in a housing (also plenum or air box called) can be accommodated or be open.
In internal combustion engines with external mixture formation, the intake tract also contains a carburetor or an injection system and their auxiliary units. In engines with a supercharger , the turbocharger or compressor are also part of the intake system. With these designs, there may also be overpressure in the intake tract. An intake tract must be completely tight (it must not "draw air") in order to ensure that the internal combustion engine and any vacuum-operated auxiliary drives such as the brake booster work properly .
- Richard van Basshuysen, Fred Schäfer: Handbook Internal Combustion Engine Basics, Components, Systems, Perspectives. 3rd edition, Friedrich Vieweg & Sohn Verlag / GWV Fachverlage GmbH, Wiesbaden, 2005, ISBN 3-528-23933-6