ECM Operating Conditions Sensed (Inputs)

• A/C "ON" or "OFF"
• Engine Coolant Temperature
• Ambient Temperature
• Barometric Press. (BARO)
• Brake "ON" or "OFF"
• Cruise Control "ON" or "OFF"
• Differential Press. (Eng. Vacuum)
• Distributor Reference
• Crankshaft Position
• Engine Speed
• EGR Vacuum
• Engine Cranking
• Engine Detonation (ESC)
• Exhaust Oxygen (O2)
• Manifold Absolute Press. (MAP)
• Mass AirFlow (MAF)
• Manifold Air Temperature (MAF)
• Park/Neutral Sw. Position (P/N)
• System Voltage
• Throttle Position (TPS)
• Transmission Gear Position
• Vehicle Speed (VSS)

Fig 1: Schematic of Computer Command Control System

Fig 2: Sectional View of Mixture Control Solenoid. Note air bleed above main metering rod.