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Home >> Volkswagen >> 2004 >> GTI Base, Standard >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 2 (2.8L - Engine Mechanical, Engine Code: BDF) >> 26 - Exhaust System, Emission Controls >> Secondary air system >> Function
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Secondary air system: Function

WARNING: This page is about a different variant/trim than selected.

During cold starting the secondary air system blows air in behind the exhaust valves. This produces an oxygen rich exhaust gas, causes afterburning and reduces the heating-up phase of the catalytic converter. Activation is performed by the Motronic Engine Control Module J220 via the Secondary Air Injection (AIR) pump relay J299 to the combi-valve.

Checking secondary air system → Secondary air system, checking  .

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