What Causes Low Secondary Air Flow in Mercedes-Benz 272 Engine?

[DeDakota]

Secondary air injection system malfunction. The user needs to replace both the air injection actuator and air pump to resolve the issue. This occurs because while the power terminals of the air pump receive electricity, internal breakdown of the air injection actuator causes continuous connection between the motor power line and the 50A fuse, leading to motor burnout due to prolonged operation. Components of secondary air injection system: The secondary air injection system consists of an air pump, air injection control valve, air injection actuator, and connecting pipes. The engine control unit regulates the air pump and control valve through the actuator, which simultaneously feeds back system operation status to the ECU. Automotive maintenance precautions: Never open the radiator cap when the engine is hot, as escaping coolant or high-temperature steam may cause burns. After the engine cools, check that the coolant level is between FULL and LOW marks. If not, add distilled water, purified water, or antifreeze - the final level must not exceed the FULL mark.