Abstract: A method for operating an exhaust gas mass flow sensor which is used, in particular, in exhaust gas mass flows of motor vehicles has an operating mode and a cleaning mode. In an operating mode, the exhaust gas mass flow sensor is operated at an operating temperature. In a cleaning mode, the exhaust gas mass flow sensor is changed over for the purpose of cleaning a measurement region and is cleaned at a cleaning temperature which is higher than the operating temperature.

Abstract: A measuring instrument for measuring mass of a flowing medium in which a measuring body extends across the flowing medium and has a rectangular flow channel through which the medium flows. The flow channel has a constricted inlet, a central portion with parallel sides and a widened outlet. A measuring element is supported in the measuring body such that the medium flows thereon. The measuring element carries temperature and heating sensors.

Abstract: An air-mass sensor having an air mass sensor module provided with two temperature sensors (6, 7) and two heat sensors (4, 5) which are incorporated into two separately acting bridges (I, II) whose bridge output signals (Umv, Umh, Umq) are supplied to a microprocessor (16) incorporated on a common support with the air-mass sensor module. The microprocessor (16) is calibrated such that crude bridge signals (Usv, Ush, Usq) measured in a base mode are inscribed in support places (x1, x2, x3) of support place tables (St2, St3). A customer characteristic curve is filed in the form of measurement points (m1, m2, m3) in the support place tables (St2, St3) and are utilized to adjust the crude bridge signals.