The invention relates to a method for starting an internal combustion engine, the exhaust gas system of which is equipped with an electrically heatable lambda sensor and a catalytic converter with an oxygen reservoir. The combination of method steps according to the invention allows the internal combustion engine to be started with an optimal raw emission reduction directly after a cold start and an optimal pollutant conversion in the warm-up phase. The invention likewise relates to a motor vehicle with an internal combustion engine comprising an exhaust gas system having an electrically heatable lambda sensor and a catalytic converter with an oxygen reservoir, and comprising a controller, wherein the controller is designed to carry out the method according to the invention.