EFI Acronyms and Abbreviations
#/Hr - Pounds per Hour or PPH
ABS - Anti-lock Braking System
A/C - Air Conditioning
AE - Acceleration Enrichment
AFPR - Adjustable Fuel Pressure Regulator
AFR - Air Fuel Ratio
ATDC - After Top Dead Center
ALDL - Assembly Line Diagnostic Link
BARO - Barometric Pressure
BBL - Barrel
BCM - Body Control Module
BDC - Bottom Dead Center
BIN - Binary
BLM - Block Learn Multiplier
BSFC - Brake Specific Fuel Consumption
BPC - Base Pulse Constant
BPW - Base Pulse Width
BTDC - Before Top Dead Center
CAT - Catalytic Converter
CCI - Computer Controlled Ignition
CCP - Charcoal Cannister Purge
CDI - Capacitive Discharge Ignition
CEL - Check Engine Light
CFI - Cross-Fire Injection
CLT - Closed Loop Term
CNP - Coil Near Plug
CTS - Coolant Temperature Sensor
DC - Duty Cycle
DE - Deceleration Enleanment
DFCO - Decel Fuel Cut Off
DIS - Distributorless Ignition System
DRP - Distributor Reference Pulse

EAC Valve An abbreviation for Electric air control valve. This is the GM version of a diverter air gulp valve, providing three functions in a single valve
•the normal diverter valve function, i.e., it diverts air on rapid increase in manifold vacuum;
•it relieves pressure by diverting air to the air cleaner when the air injection system pressure exceeds a certain set level;
•being solenoid-controlled, it allows air to be diverted under any desired operating mode.

ECM - Engine Control Module
ECT - Engine Coolant Temperature
EGR - Exhaust Gas Recirculation
EGT - Exhaust Gas Temperature
EPROM - Eraseable Programmable Read-only Memory
ESC - Electronic Spark Control, knock detection & retard
EST - Electronic Spark Timing, SA control
FAR - Fuel Air Ratio
FPR - Fuel Pressure Regulator
Ft/Lb - Foot Pounds
GPS - Grams Per Second
Gms/Sec - Grams per Second
HEI - High Energy Ignition
HP - Horse Power
IAC - Idle Air Control
IAT - Intake Air Temperature
INT - Integrator
Km - KiloMeters
Km/L - Kilometers per Litre
KPa - KiloPascals
KPH - Kilometers Per Hour
LM - Launch Mode
LSA - Lobe Separation Angle
MAF - Mass Air Flow
MAP - Manifold Absolute Pressure
MAT - Manifold Air Temperature
MPG - Miles Per Gallon
MPH - Miles Per Hour
MPFI - Multi Port Fuel Injection
NB - Narrow Band O2 sensor
O2 - Oxygen Sensor
P/S - Power Steering
PCM - Powertrain Control Module
PCV - Positive Crankcase Ventilation
PE - Power Enrichment
PPH - Pounds Per Hour
PROM - Programmable Read-only Memory
PSI - Pounds per Square Inch
PW - Pulse Width
PWM - Pulse Width Modulation
RPM - Revolutions Per Minute
SA - Spark Advance
SD - Speed Density
SES - Service Engine Soon
TACH - Tachometer
TBI - Throttle Body Injection
TCC - Torque Converter Clutch
TCM - Transmission Control Module
TDC - Top Dead Center
TF - Throttle Follower
TPS - Throttle Position Sensor
TSA - total spark advance
VAC - Vacuum
VAFPR - Vacuum Adjusted Fuel Pressure Regulator
VATS - Vehicle Anti-theft System
VE - Volumetric Efficiency
VRFPR - Vacuum Referenced Fuel Pressure Regulator
VSS - Vehicle Speed Sensor
WB - Wide Band O2 sensor
WOT - Wide Open Throttle