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Home >> Volkswagen >> 2005 >> Golf (1J1) L4-2.0L (AVH) >> Repair and Diagnosis >> Powertrain Management >> Emission Control Systems >> Air Injection >> Description and Operation >> Function - I
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Function - I



Function
Air is blown behind the exhaust valves by the Secondary Air Injection (AIR) system during a cold start. Thereby, the emission gas is enriched with oxygen, initiating a secondary combustion and thereby shortening the warm-up phase of the catalytic converter. Activation occurs from Motronic Engine Control Module (ECM) -J220- via Secondary Air Injection (AIR) pump relay -J299-.

NOTE:
- Always replace seals and gaskets.
- Vacuum lines and hose connections must not have leaks.
- Vacuum hoses must not be clogged or kinked.
- For the electric components to work properly, a voltage of at least 11.5 V is required.
- Components marked with * are tested via On Board Diagnostic (OBD), Diagnostic mode 3: Check DTC memory.

Removing and installing Secondary Air Injection (AIR) system components.
Check secondary air system for proper seal.