Secondary Air Injection Sensor 1 - G609-, Checking: General Description
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The secondary air injection system injects air into the exhaust on a cold-start of the engine for 45 - 100 s and serves to quickly heat the catalytic converter(s) for improved emissions. A pressure based secondary air diagnostic function is used. In this system, the signal from the Secondary Air Injection Sensor 1 -G609- is evaluated by the Engine Control Module -J623-. The injected air quantity is determined from the pressure level.