Originally Posted by GraphiteGhost

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There is also the little blue check valve sourced here (1991-2015 Mercedes-Benz Check Valve 002-140-84-60 | MB OEM Parts) that could also be the issue, check this post for information (P0410 - Secondary Air Injection Problem - CrossfireForum - The Chrysler Crossfire and SRT6 Resource), POST #4 (partially states): The little BLUE check valve #12 in the illustration is a known issue with the Secondary air injection system. It is prone to sticking closed. This check valve is between the vacuum control solenoid and the diverter valves which allow fresh air to flow to the exhaust. When this valve is stuck it can not open the diverters. This sets the P0410 code, due to the O2 sensors not seeing a change from the fresh air being injected. The valve is located @ (passenger) front corner of the engine, under the engine cover. Bright Blue valve in the vacuum hose. If you change it yourself pay close attention to the position of the arrow (molded into the plastic) it indicates direction of flow. Good luck!


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