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Engine Control Module: Description and Operation

Powertrain Control Module (PCM):






The Powertrain Control Module (PCM) performs the following functions:
- accepts information 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
- sends out a command to the fuel injectors to meter the appropriate quantity of fuel
- determines and compensates for the age of the vehicle and its uniqueness
- automatically senses and compensates for changes in altitude (for example, from sea level to mountains)