Secondary Air Injection System, through 05.07

Secondary Air Injection System, through 05.07

The Secondary Air Injection (AIR) system heats up the engine faster, and thereby the catalytic converter achieves operation readiness earlier after a cold start.

Function

Due to the rich mixture during the cold start phase, the exhaust emissions contain an increased level of unburned hydrocarbons. The AIR system improves the secondary oxidation within the catalytic converter, thereby reducing harmful emissions. The heat released by secondary oxidation shortens the start up time of the catalytic converter considerably, as well as significantly improves emissions quality during the cold-running phase.

In the cold start phase, the Engine Control Module (ECM) (J623) controls the AIR pump via the pump relay. The stream of air from the Secondary Air Injection (AIR) pump opens the combination valves and allows air to flow into the exhaust system before the catalytic converter.