Abstract: A process and a device for producing a finely distributed fuel mist, especially for preparing an easily burnable fuel-air mixture for the heater (25) of a motor vehicle. In a chamber (1) which is partially filled with a fuel (3), an ultrasonic oscillator (2) is immersed in the liquid fuel (3) and a fuel column with an exposed fuel surface (4) is formed above the ultrasonic oscillator (2). The ultrasonic oscillator (2) is operated with a frequency such that extremely small fuel particles (5) are detached at the surface (4) of the and a fuel mist is formed in the chamber (1). In a heater, the device in located in an air flow stream which creates a negative pressure that draws the fuel mist out of the chamber opening (6).

Abstract: The invention relates to a motor vehicle heating system (10) which is embodied in such a way as to be operated by liquid fuel, and comprises a fuel pump (16) and an electromagnetically actuated fuel valve (84; 200) which is arranged downstream from the fuel pump. According to the invention, the electromagnetically actuated fuel valve (84; 200) is embodied in such a way as to pre-heat fuel. The invention also relates to a method for pre-heating liquid fuel for a motor vehicle heating system, whereby the waste heat of an electromagnetically actuated fuel valve (84; 200) is used to pre-heat the fuel.