Engine Control Module: Description and Operation

Powertrain Control Module (PCM):

The Powertrain Control Module (PCM) performs the following functions:
- The PCM accepts input from various engine sensors to compute the required fuel flow rate necessary to maintain a prescribed air/fuel ratio throughout the entire engine operational range.
- Then the PCM outputs a command to the fuel injectors to meter the appropriate quantity of fuel.
- The PCM determines and compensates for the age of the vehicle and its uniqueness, also automatically senses and compensates for changes in altitude (i.e. from sea level to mountains).