Emission control device diagnosing method for cleaning exhaust gas stream of e.g. diesel engine in motor car, involves determining reaction of pressure of flow of reducing agent, and interpreting reaction for diagnosing control device

摘要

The method involves conveying a volumetric flow (15) of a reducing agent (17) required for selective catalytic reduction to a pump device (13) and downstream of an exhaust gas stream assigned dosing device (19). A control signal (3) of an emission control device (5) is changed or set. Reaction pressure of the volumetric flow of the reducing agent between the pump device and the dosing device is determined based on the change of the control signal. The reaction for diagnosing the emission control device is interpreted. An independent claim is also included for an emission control device comprising a pump device.