A

A/C

Air Conditioning

AC

Alternating Current

ACL

Air Cleaner

ADJ

Adjust

A/F

Air/Fuel (Ratio)

AIR

Secondary Air Injection

Alt

Altitude

AMP

Ampere(s)

AM/FM

AM/FM Stereo

Ant

Antenna

AP

Accelerator Pedal

ASM

Assembly

AT

Automatic Transmission

ATDC

After Top Dead Center

Auth

Authority

Auto

Automatic

B

B+

Battery Positive Voltage

BARO

Barometric (pressure)

Bat

Battery

BP

Back Pressure

BTDC

Before Top Dead Center

C

°C

Degrees Celsius

CAC

Charge Air Cooler

Calif

California

CCOT

Cycling Clutch Orifice Tube

CD

Compact Disc

CFI

Continuous Fuel Injection

CFM

Cubic Feet Per Minute

CID

Cubic Inch Displacement

CKP

Crankshaft Position

CL

Closed Loop

cm

Centimeters

CMP

Camshaft Position

CO

Carbon Monoxide

Coax

Coaxial

Conn

Connector

Conv

Converter

CPP

Clutch Pedal Position

CPS

Central Power Supply

Crank

Crankshaft

CTP

Closed Throttle Position

CV

Constant Velocity

Cyl

Cylinder(s)

D

DC

Direct Current

DFI

Direct Fuel Injection

Diff

Differential

DI

Distributor Ignition

Dist

Distributor

DLC

Data Link Connector

DTC

Diagnostic Trouble Code

DTM

Diagnostic Test Mode

DVM

Digital Voltmeter

E

EAC

Electric Air Control

EAS

Electric Air Switching

ECL

Engine Coolant Level

ECM

Engine Control Module

ECT

Engine Coolant Temperature

ECU

Engine Calibration Unit (PROM)

EEPROM

Electronically Erasable Programmable Read Only Memory

EFE

Early Fuel Evaporation

EGR

Exhaust Gas Recirculation

EGR TVV

Exhaust Gas Recirculation Thermal Vacuum Valve

EI

Electronic Ignition

EM

Engine Modification

EPROM

Erasable Programmable Read Only Memory

ESC

Electronic Spark Control

ESD

Electrostatic Discharge

ETR

Electronically Tuned Receiver

EVAP

Evaporative Emission

Exh

Exhaust

F

°F

Degrees Fahrenheit

FC

Fan Control

FED

Federal (all the United States except California)

G

gal

Gallon

GAW

Gross Axle Weight

GAWR

Gross Axle Weight Rating

GCWR

Gross Combination Weight Rating

Gen

Generator

Gov

Governor

g

gram

gnd

Ground

GVW

Gross Vehicle Weight

GVWR

Gross Vehicle Weight Rating

H

Harn

Harness

HC

Hydrocarbons

HD

Heavy Duty

Hg

Mercury

Hi Alt

High Altitude

HO2S

Heated Oxygen Sensor

hp

Horse Power

I

IAC

Idle Air Control

IAT

Intake Air Temperature

IC

Ignition Control

ICM

Ignition Control Module

ID

Identification or Inside Diameter

IFI

Indirect Fuel Injection

ign

Ignition

ILC

Idle Load Compensator

INJ

Injection

INT

Intake

I/P

Instrument Panel

IPC

Instrument Panel Cluster

ISC

Idle Speed Control

K

kg

Kilogram

km

Kilometer

km/h

Kilometers per hour

kPa

Kilopascals

KS

Knock Sensor

kV

Kilovolts

L

lb

Pound(s)

lb ft

Pound feet (torque)

lb in

Pound inch (torque)

L

Liter (engine displacement)

LF

Left Front

LH

Left Hand

LR

Left Rear

LS

Left Side

M

MAF

Mass Air Flow

Man

Manual

MAP

Manifold Absolute Pressure

MAT

Manifold Air Temperature

Max

Maximum

MC

Mixture Control

MDP

Manifold Differential Pressure

MFI

Multi-Port Fuel Injection

mi

Mile(s)

MIL

Malfunction Indicator Lamp

Min

Minimum

ml

Milliliter

mm

Millimeter

mpg

Miles per Gallon

mph

Miles per Hour

MST

Manifold Surface Temperature

mV

MilliVolt

N

NC

Normally Closed

N·m

Newton-meter (torque)

NO

Normally Open

NOx

Oxides of Nitrogen

NVRAM

Non-Volatile Random Access Memory

O

OBD

On-Board Diagnostics

OC

Oxidation Converter (Catalytic)

OD

Outside Diameter

OL

Open Loop

O2

Oxygen

O2S

Oxygen Sensor

oz

Ounce(s)

P

PAIR

Pulsed Secondary Air Injection

P/B

Power Brakes

PCM

Powertrain Control Module

PCV

Positive Crankcase Ventilation

PNP

Park/Neutral Position

PRESS

Pressure

PROM

Programmable Read Only Memory

PS

Power Steering

psi

Pounds per Square Inch

pt

Pint

PTO

Power Take Off

PWM

Pulse Width Modulated

Q

qt

Quart(s)

R

RAM

Random Access Memory

Ref

Reference

RF

Right Front

RFI

Radio Frequency Interference

RH

Right Hand

ROM

Read Only Memory

RPM

Engine Speed (Revolutions Per Minute)

RPO

Regular Production Option

RR

Right Rear

RS

Right Side

RTV

Room Temperature Vulcanizing (sealer)

RVB

Rear Vacuum Brake

RVR

Response Vacuum Reducer

S

SAE

Society of Automotive Engineers

Sec

Secondary

SI

System International

sol

Solenoid

SPEC

Specification

Speedo

Speedometer

SPL

Smoke Puff Limiter

SRI

Service Reminder Indicator

SRT

Service Readiness Test

ST

Scan Tool

syn

Synchronize

T

TAC

Throttle Actuator Control

Tach

Tachometer

TCC

Torque Converter Clutch

TCM

Transmission Control Module

TEMP

Temperature

TDC

Top Dead Center

Term

Terminal

Thermo

Thermostatic Air Cleaner

TP

Throttle Position

TRANS

Transmission

TV

Throttle Valve

TVRS

Television and Radio Suppression

TVV

Thermal Vacuum Valve

TWC

Three Way Converter (Catalytic)

TWC+OC

Three Way + Oxidation Converter (Catalytic)

U

U-Bolt

Universal Bolt

U-Joint

Universal Joint

V

V6

Six Cylinder Engine, V-Type

V8

Eight Cylinder Engine, V-Type

V

Volt(s)

V-ref

ECM Reference Group

Vac

Vacuum

VAF

Volume Air Flow

VDOT

Variable Displacement Orifice Tube

VIN

Vehicle Identification Number

VR

Vacuum Regulator

VRV

Vacuum Reducer Valve

VSS

Vehicle Speed Sensor

W

W/

With

W/B

Wheel Base

W/O

Without

WOT

Wide Open Throttle

WU-OC

Warm Up Oxidation Converter (Catalytic)

WU-TWC

Warm Up Three Way Converter (Catalytic)