A method for determining a value representative of the pressure in a combustion chamber of an internal combustion engine, includes the following steps: i. measuring the vibration level (2) of the internal combustion engine with an accelerometer placed on the engine block of the internal combustion engine, ii. integrating a value from the signal (2) provided by the accelerometer in a window (t1, t2) delimited as a function of the position of the crankshaft of the internal combustion engine, iii. supplying the result of the integration (A1) as a value representative of the pressure, characterized in that the signal (2) provided by the accelerometer in step “i” is integrated while being raised to a power greater than 1 by a predetermined exponent.