A vehicle burner (6) for heating a gas flow (14) in a motor vehicle is provided with a fuel pump (10) for delivering a fuel to an injection nozzle (11) that can be actuated for injecting the fuel into a combustion chamber (7), with an air delivery device (16) for delivering air to the combustion chamber (7), with a control (17) for operating the. A vehicle burner (6), which is coupled with the fuel pump (10), with the air delivery and/or air regulating device (16) and with the injection nozzle (11). Burner waste gas, which is generated during the operation of the. A vehicle burner (6) by the reaction of fuel with air in the combustion chamber (7), is used to heat the gas flow (14). To increase efficiency, a control (17) determines a quantity of fuel, a quantity of air and a fuel pressure as a function of a presettable heat output. The control (17) actuates the air delivery and/or air regulating device (16) for setting the quantity of air determined, the fuel pump (10) for setting the fuel pressure determined and the injection nozzle (11) for setting the quantity of fuel determined to set the predetermined heat output.