METHOD FOR OPERATING AN EXHAUST BURNER, APPARATUS FOR PERFORMING SUCH A METHOD, AND MOTOR VEHICLE

A method for operating an exhaust burner with a secondary air system downstream of a combustion engine of a motor vehicle. The method includes: activating an ignition device as a function of a release condition, the ignition device being heated up to a specifiable target temperature; metering fuel at a first time point into a combustion chamber of the exhaust burner at a first injection frequency using an injection valve, and the combustion chamber not being actively supplied with air; setting a first target air-mass flow using a secondary air system at a further, second time point, wherein the air-mass flow is increased strictly monotonically; controlling the air-fuel ratio to a first target air-fuel ratio as a function of a lambda sensor starting from the second time point, and metering fuel at a second injection frequency; setting a second target air-mass flow at a further, third time point.