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Secondary Air Pump Replacement

Model: BMW Serie 3 E92, E90, E91 - Years 2005-2013
Part: Pump

During the cold start phase of a gasoline engine, a particularly rich mixture is necessary, meaning an excess of fuel, which leads to the formation of large amounts of carbon monoxide and unburned hydrocarbons. To reduce these substances, air is blown directly behind the exhaust valves into the exhaust manifold during cold starting, generating a combustion zone for the harmful substances that heats the catalyst to accelerate the lambda regulation. This pump is located in front of the coolant reservoir, and to replace it, simply disconnect the hoses, the power supply connector, and the support rubber mounts.

Updated on 19 February 2026 by ScegliAuto

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