Powertrain Management: Description and Operation

PURPOSE
Modern engine management and control systems electronically regulate the air/fuel mixture, idle speed and ignition timing to achieve optimum [1]engine performance.

INFORMATION STRUCTURE
Information in POWERTRAIN MANAGEMENT is divided into the following five major topics:

Computers and Control Systems
Addresses the on-board computer system and components as related to engine management. Consult this section for information regarding on-board diagnostics, sensor inputs, computer outputs, etc.

Emission Control Systems
Addresses emission related 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 Delivery and Air Induction
Focuses on systems and components related to fuel and intake air delivery. Does NOT include information regarding electronic engine controls.

Ignition System
Focuses on primary and secondary ignition systems and components.

Transmission Control Systems
Focuses on systems that electronically control all or part of the automatic transmission operation. These systems usually work in conjunction with the electronic engine control systems. This section does NOT include information regarding mechanical repairs or overhaul procedures relating to the transmission.

[1] Optimum performance means the best possible compromise between the demands of high power, low fuel consumption, and the cleanest possible exhaust emissions.