Common Terms From FAST

[CPG Marketing]

CAN - Controller Area Network
An electronic hardware standard that permits simplified, high speed interfacing between electronic control units in a vehicle environment. For example, the FAST™ XFI™ system can communicate with the FAST™ Transmission Controller through the use of its CAN BUS.

ECU - Engine Control Unit
A vehicle-mounted engine control computer that varies engine behavior such as fuel injector activity, idle speed, air/fuel ration, ignition timing, etc. based on input from an array of sensors including O2 TPS, and others.

EFI - Electronic Fuel Injection
A means of injecting fuel into the intake manifold of an internal-combustion engine using various types of fuel injectors that are controlled by an ECU (see below). EFI takes many forms, including throttle body injection (TBI) where a carburetor-like throttle body houses the injector(s), and port injection, where rail-mounted fuel injectors feed into each runner of the engine intake manifold.

MAP - Manifold Absolute Pressure
An engine sensor that measures intake manifold vacuum. Generally measured in bars, MAP data is used to measure engine load, which in turn allows the ECU to regulate engine behavior such as fuel supply and air/ratio.

O2 - Oxygen
Commonly used either as shorthand term for an oxygen sensor or to describe oxygen as it is measured in engine sexhaust gases. O2 data is primarily used by an ECU for the purpose of regulating the engine air/fuel ratio.

TCU - Transmission Control Unit
A vehicle-mounted transmission control computer that varies transmission behavior such as shift points, shift firmness, downshifting and torque converter lockup based on engine load, vehicle speed and other variables.

TPS - Throttle Position Sensor
An electronic sensor, generally mechanically linked to the throttle body of an EFI engine for the purpose of measuring how far the throttle is opened when the vehicle operator steps on the vehicle throttle pedal. Throttle position data is generally expressed in terms in terms of percentage and plays an important role in many ECU functions, not to mention determining when power adders such as nitrous are deployed.

TPS - Throttle Position Sensor
An electronic sensor, generally mechanically linked to the throttle body of an EFI engine for the purpose of measuring how far the throttle is opened when the vehicle operator steps on the vehicle throttle pedal. Throttle position data is generally expressed in terms of percentage and plays an important role in many ECU functions, not to mention determining when power adders such as nitrous are deployed.

VATS - Vehicle Anti-Theft System
An anti-theft circuit built into most GM fuel injection ECUs made after 1989. VATS must be bypassed with a special chip in order for some EFI engines to run when swapped from one vehicle to another.

VSS - Vehicle Speed Sensor
An electronic speed sensor, generally mounted in the output shaft housing of a transmission (a VSS may also be mounted at a wheel or other location). VSS data is used by both ECUs and TCUs for a variety of purposes, including torque converter lockup, downshifting, etc.