Abstract: The invention relates to a method for detecting an unsealed location in a heat recovery system of an internal combustion engine of a motor vehicle. The heat recovery system has at least one working medium, in particular a combustible working medium, and a working medium circuit with at least one evaporator, a pump, and at least one expansion machine to allow an early and reliable detection of leakages in the evaporator.

Abstract: The invention relates to a method for detecting an unsealed location in a heat recovery system of an internal combustion engine of a motor vehicle. The heat recovery system has at least one working medium, in particular a combustible working medium, and a working medium circuit with at least one evaporator, a pump, and at least one expansion machine to allow an early and reliable detection of leakages in the evaporator.

Abstract: A method for detecting a leaking point in a heat recovery system of an internal combustion engine of a motor vehicle, wherein the heat recovery system includes a combustible working medium and a working medium circuit with an evaporator, a pump and an expansion machine. The recirculated exhaust gas of the engine flows through or around the evaporator which is arranged in an exhaust-gas return line. At least one oxidation catalytic converter is arranged in an exhaust gas line of the engine. A first temperature sensor is arranged in the exhaust gas line upstream and a second exhaust gas temperature sensor is arranged downstream of the oxidation catalytic converter. Temperatures of the exhaust gas are measured with these temperature sensors during operation of the engine in the exhaust gas line upstream and downstream of the oxidation catalytic converter.

Abstract: Temperatures of exhaust gas upstream and downstream of an oxidation catalytic converter in an exhaust gas line of an internal combustion engine are measured and the differences analyzed to detect a leakage in the EGR evaporator.