Method and device for heating an exhaust pipe in a motor vehicle

A method for heating an exhaust pipe in a motor vehicle, comprising the steps of:

• injecting a predetermined quantity of fuel and comburent into an injection area (A) inside an exhaust pipe in a motor vehicle;
• performing a plurality of spark cycles in succession, wherein each spark cycle comprises:
• generating at least one spark between ends of a pair of electrodes located in proximity to the injection area to start a combustion;
• detecting a value of a representative quantity representing an ionization current flowing between said ends of the pair of electrodes following an extinction of said at least one spark;
• comparing said value of the representative quantity representing the ionization current with a preset reference value and determining:
• a presence of combustion in the spark cycle if said value of the representative quantity is greater than said preset reference value;
• an absence of combustion in the spark cycle if said value of the representative quantity is less than said preset reference value;
• generating, in the same spark cycle or in a subsequent cycle, information relating to the absence or presence of combustion according to the outcome of said comparison.