A method for processing a signal of a pressure measuring device inside an internal combustion engine, the device including: a pressure measuring sensor supplying an output voltage signal (SB), and a processing unit connected to the pressure measuring sensor, the method including the following steps: I. calculating a duration (Dt1) between a first time (t0) corresponding to a first combustion pressure peak (P0) and a second time (t1) corresponding to a second combustion pressure peak (P1), consecutive to the first combustion pressure peak (P0), II. calculating a correction start time (tc1) defined according to the previously calculated duration (Dt1), III. measuring a value of the signal (VOFF1) at the correction start time (tc1), IV. correcting the signal, on the basis of the correction start time (tc1) in relation to a reference value (VREF) and obtaining a first processed signal (S) such that: S=SB−VOFF1+VREF.