Powertrain Management: Description and Operation
PURPOSE
Computerized Engine Control (CEC) Systems electronically regulate the air/fuel mixture, idle speed and ignition timing to achieve optimum [1] engine performance.
INFORMATION STRUCTURE
Information in this section is divided into the following four major sub-headings:
Computers Addresses the on-board computer system
And Control and components as related to engine management.
Systems Consult this section for information regarding on-board diagnostics, sensor inputs, computer outputs, etc.
Emission Addresses emission related
Control Devices systems and components only. Includes (but is not limited to) Exhaust Gas Recirculation (EGR) systems, Evaporative Emission (EVAP) systems, Positive Crankcase Ventilation (PCV) systems, Exhaust Emission controls, Air Injection Systems (AIS), etc.
Fuel Supply And Focuses on systems and components related
Air Induction to fuel and intake air delivery. Does NOT
Systems include information regarding electronic engine controls.
Ignition System Focuses on primary and secondary ignition systems and components. Does NOT include information regarding electronic engine controls.
Computers Addresses the on-board computer system
And Control and components as related to engine management.
Systems Consult this section for information regarding sensor inputs, computer outputs, etc.
[1] Optimum performance means the best possible compromise between the demands of high power, low fuel consumption, and the cleanest possible exhaust emissions.