Secondary Air Injection (AIR) system: 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 module. Activation occurs from Motronic Engine Control Module (ECM) -J220- via Secondary Air Injection (AIR) Pump Relay -J299- to Secondary Air Injection (AIR) Solenoid Valve -N112- (change-over valve) and to the combination valves.

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 electrical components to work properly, a voltage of at least 11.5 V is required.

Components marked with * are tested via On Board Diagnostic (OBD). Refer to Diagnostic mode 3: Check DTC Memory .

Removing and installing Secondary Air Injection (AIR) system components. Refer to Secondary Air Injection (AIR) system components, removing and installing .

Checking secondary air system for proper seal. Refer to Secondary Air Injection (AIR) system, checking for proper seal .