Engine Controls - Theory & Operation

• Introduction
• Computerized Engine Controls
  • Engine Control Module (ECM)
  • Input Devices
    • Notes
    • Air Conditioning Signal
    • Battery Voltage Signal
    • Crankshaft Position (CKP) Sensor
    • Engine Coolant Temperature (ECT) Sensor
    • Heated Oxygen Sensor (HO2S)
    • Ignition On Signal
    • Idle Override Signal
    • Intake Air Temperature (IAT) Sensor
    • Mass Airflow (MAF) Sensor
    • Park/Neutral Position (PNP) Switch
    • Throttle Position (TP) Sensor
  • Output Signals
    • Notes
    • Air Injection Relay
    • Malfunction Indicator (CHECK ENGINE) Light
    • Heated Oxygen Sensor (HO2S) Relay
    • Idle Air Control (IAC) Valve
    • Idle Fuel Control
• Fuel System
  • Fuel Delivery
    • Fuel Pump Module (FPM)
    • Fuel Pressure Regulator
    • Inertia Fuel Shutoff Switch (IFSS)
  • Fuel Control
    • Air/Fuel Ratio Corrections
    • After-Start Enrichment
    • Cranking Enrichment
    • Demand (Engine Load) Corrections
    • Fuel Injectors
    • Heated Oxygen Sensor (HO2S) Relay
    • Idle Fuel Control
    • Temperature Enrichment
    • Voltage Corrections
  • Idle Speed
    • Idle Air Control (IAC) Valve
• Ignition System
• Emission Systems
  • Air Injection System
  • Crankcase Ventilation System
  • Exhaust Gas RECIRCULATION (EGR)
  • Fuel Evaporative System
• Self-Diagnostic System
  • ECM
  • Malfunction Indicator Light (Mil)