A method for checking an exhaust-gas section of a combustion engine for a leak, including the following: introducing secondary air into the exhaust-gas section of the combustion engine via a secondary-air valve, determining a measured value that indicates the magnitude of the relative pressure changes due to the expelling of exhaust gas from the combustion engine upstream from the secondary-air valve, and detecting the leak in the exhaust-gas section as a function of the measured value.