Engine Control Module: Description and Operation

The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:
^ Fuel control
^ Ignition Control (IC)
^ Knock Sensor (KS) system
^ Automatic transmission shift functions
^ Manual Transmission: 1-4 Upshift and Reverse Inhibit
^ Cruise Control Enable (if so equipped)
^ Generator
^ Evaporative Emission (EVAP) Purge
^ A/C Clutch Control
^ Cooling Fan Control
^ Secondary Air Injection (AIR)