As with naturally aspirated engines, engines equipped with turbochargers must have precise measurements of airflow, temperature and density to correctly calculate fuel injection and, in the case of gasoline engines, ignition time. For this reason, the ECM (Engine Control module) uses several sensors to perform these calculations constantly.
The actual pressure of the intake manifold is measured by the Manifold Absolute Pressure (MAP) sensor. If the ECM detects that the measured pressure is greater than the ordered pressure, the diagnostic code P0236 OBDII will be established. It should be noted that this code must be corrected as soon as possible, thus preventing future damage to the Catalytic Converter as well as risks of overfeeding.