If you have discussed Fiero's with other Fiero nuts, you've probably noticed that a lot of abbreviations were used. Here is a list and a short explanation of the most commonly used abbreviations.

ALDL Assembly Line Diagnostic Link.
Used at assembly to evaluate Computer Command Control, and for service to flash the "Service Engine Soon" or "Check Engine" light if there are trouble codes. It's also used by "Scan tools" to obtain ECM serial data.

C/L Closed Loop
Describes ECM fuel control when using oxygen sensor information.

CTS Coolant Temperature Sensor
Device that senses the engine coolant temperature, and passes that information to the Engine Control Module.

DIS Direct Ignition System
Produces the ignition spark without the aid of an ignition distributor.

ECM Engine Control Module
A metal case (located in passenger compartment) containing electronic circuitry which electrically controls and monitors air/fuel and emission systems on computer command control and turns "ON" the "Service Engine Soon" or "Check Engine" light when a malfunction occurs in the system.

EFI Electronic Fuel Injection
Computer Command Control using throttle body fuel injection.

EGR Exhaust Gas Recirculation
Method of reducing NOx emission levels by causing exhaust gas to be added to air/fuel mixture in combustion chamber, thus cooling combustion.

IAC Idle Air Control
A valve installed in the throttle body of fuel injected systems and controlled by the ECM to regulate idle speed.

ISC Idle Speed Control
Regulates throttle valve position to control idle speed. Idle speed is controlled by the ECM and is not adjustable.

MAP Manifold Absolute Pressure (Sensor)
Reads pressure changes in intake manifold with reference to zero pressure. It puts out a voltage which is highest when the pressure is highest. The maximum voltage is between 4 and 5 Volts.

MAT Manifold Air Temperature (Sensor)
Measures temperature of air in the intake manifold.

MFI Multiport Fuel Injection
Individual injectors for each cylinder are mounted in the intake manifold. The injectors are fired in groups rather than individually.

M/C Mixture Control (Solenoid)
Device, installed in carburator, to regulate the air/fuel ratio.

O/L Open Loop
Describes ECM fuel control without use of oxygen sensor information.

TBI Throttle Body Injection (Unit)
Unit, controlled by ECM to supply precise air/fuel mixture into the intake manifold.

TPS Throttle Postion Sensor
Device that tells the ECM the throttle position.

VIN Vehicle Identification Number
Registration number that uniquely identifies a vehicle.

VSS Vehicle Speed Sensor
Sensor which sends vehicle speed information (pulses per mile) to the ECM.