Complementary device for the tuning of a internal combustion engine of a vehicle

A supplementary engine control device comprises a microcontroller, a non-volatile memory, an interface unit, an analog input and an analog output. The interface unit can connect the microcontroller to a computer bus, and enables the microcontroller to listen to data on the bus. The analog input is connected to the microcontroller via an analog-to-digital converter and serves to connect the supplementary device to a probe. The analog output is connected to the microcontroller via a digital-to-analog converter and serves to connect the supplementary device to an analog input of the original engine control unit. The microcontroller is designed so as to be able to listen to data on the bus, calculate a correction of a signal applied to the analog input on the basis of a mapping stored in the memory and transmit to the analog output a corrected signal, which corresponds to the signal applied to the analog input but including said correction.