Abstract: A diagnostic system and a diagnostic method for a technical system are described with which, on the basis of the expert knowledge already necessary for the manual establishment of troubleshooting trees, the establishment of troubleshooting trees can be automated and the performance of guided troubleshooting can be assisted. Provided for this purpose are an acquisition module for systematic acquisition of all relevant status, observation, and/or measured data of the technical system, and a prioritization module for prioritizing all relevant tests, checks, or measurements, in order, in accordance with the weightings of the tests, checks, or measurements as a function of the status, observation, and/or measured data, to establish automatically a troubleshooting tree that can serve as a basis for guided troubleshooting.

Abstract: A method for detecting a leak in an intake tract of an internal combustion engine involves operating the engine at two operating points and comparing a deviation of measured mass flows from expected mass flows at the first and at the second operating points.

Abstract: A method for detecting a leak in an intake tract of an internal combustion engine including the following steps: operating the internal combustion engine at a first operating point having a rotational speed and a first pressure difference between the ambient pressure and the pressure in the intake tract of the internal combustion engine; computing a first expected mass flow into the intake tract; measuring a first mass flow into the intake tract and computing a difference between the measured first mass flow and the first expected mass flow; operating the internal combustion engine at a second operating point having the same rotational speed and a second pressure difference between the ambient pressure and the pressure in the intake tract of the internal combustion engine, the second pressure difference being different from the first pressure difference; computing a second expected mass flow into the intake tract; measuring a second mass flow into the intake tract and computing the difference between the meas