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Secondary air basis

Pierburg | Motorservice

How does the secondary air system work? What components is it made up of? What is secondary air? What does the secondary air pump do? What is the function of the secondary air valve? In this article you can find out what makes up the secondary air system and how it works.

From 01:02 to 01:25

A cold start produces pollutants such as carbon monoxide and uncombusted hydrocarbons. The secondary air system is a method of reducing these pollutants. Oxygen-rich ambient air is extracted behind the air filter. This secondary air is blown directly into the exhaust manifold after the exhaust valves.

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Burning the pollutants generates heat that brings the catalytic converter up to operating temperature faster.

From 01:40 to 02:00

The central component of the secondary air system is the secondary air pump. Secondary air pumps are high-speed, single or multi-stage blowers.

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From 02:00 to 03:00

Secondary air valves have two key functions: As non-return valves, they prevent the exhaust gas condensate and pressure peaks which occur in the exhaust tract from getting into the secondary air pump and damaging it. As cut-off valves, they ensure that air is only supplied to the manifold at the appropriate time.

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