General System Description

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 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
DEVICES 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 SUPPLY AND
AIR INDUCTION
SYSTEMS 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. Does NOT include information regarding electronic engine controls.


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


ABBREVIATIONS:


ABS Anti-lock Brake System
ACP Air Conditioning Programmer
ALDL Assembly Line Data Link (now referred to as DLC)
BCM Body Control Module
CCC Climate Control Center
CCDIC Climate Control Driver Information Center
CCP Controlled Cannister Purge
CCP Climate Control Panel
CPS Central Power Supply
CTS Coolant Temperature Sensor (now referred to as ECT)
DERM Diagnostic Energy Reserve Module (part of SIR)
DIC Driver Information Center
DLC Data Link Connector
ECM Engine Control Module (now referred to as PCM)
ECC Electronic Climate Control
ECS Electronic Spark Control (Knock)
ECT Engine Coolant Temperature
EECS Evaporative Emission Control System
EEPROM Electronically Eraseable Programable Read Only Memory
EGR Exhaust Gas Recirculation
EST Electronic Spark Timing
EVAP Evaporative Emission Control System
IAT Intake Air Temperature
ICM Ignition Control Module
I/P Instrument Panel
IPC Instrument Panel Cluster
ISC Idle Speed Control Motor
MAP Manifold Air Pressure
MIL Maintenance Indicator Lamp
PCM Powertrain Control Module (Previously called ECM)
PFI Port Fuel Injection
P/N Park/Neutral
PROM Programable Read Only Memory
PSP Power Steering Pressure
RAP Retained Accessory Power
SES Service Engine Soon
SES-MIL Service Engine Soon Maintenance Indicator Lamp
SIR Supplemental Inflatable Restraint
TCC Torque Converter Clutch
TP Throttle Position Sensor
TPCV Tank Pressure Control Valve
TPS Throttle Position Sensor
TR Transmission Range
VSS Vehicle Speed Sensor