Have any of the acronyms in your vehicle's owner's manual ever made you shake your head? Do you get confused by some of the jargon that comes out of your mechanic's mouth? Don't worry, you're not alone. There's a lot of terminology to learn when you begin servicing and maintaining your vehicle yourself, and at times it can seem daunting. This exhaustive list of all of the automotive acronyms we could think of will help you cut through the jargon and improve your understanding of cars. This list won't make you into a mechanic, but it will help you sound like one when you head to the parts counter.
This list was compiled from all the owner's manuals, and factory service manuals we had on hand, plus our own workshop manuals. Some abbreviations have more than one meaning. This list may not be complete but we are always updating it.
- A -
- AB - Air Bleed
- ABDC - After Bottom Dead Center
- ABPV or ABV - Air Bypass Valve
- ABS - Anti-lock Brake System
- AC - Alternating Current
- A/C - Air Conditioner or Air Conditioning
- ACCC - A/C Compressor Clutch
- ACCCS - A/C Clutch Cycling Switch
- ACL BI-Met - Air Cleaner Bimetal sensor
- ACL DV - Air Cleaner Duct and Valve Vacuum motor
- ACT - Air Charge Temperature sensor
- ACV - Air Control Valve
- ADS - Association of Diesel Specialists
- AEA - Automotive Electric Association
- AERA - Automotive Engine Rebuilders Association
- A/F - Air/fuel
- AFB - Aluminum Four-Barrel (carburetor)
- AFC - Air-Flow Controlled
- AFR - Air/fuel ratio
- AFS - Air Flow Sensor
- AI - Air Injection
- AICV - Air Injection Check Valve
- AIR-CHV - Air Check Valve
- AIR-DV - Air Diverter Valve
- AIR-IVV - Air Idle Vacuum Valve
- AIS - Air Injection System
- AIS - Automatic Idle Speed Motor
- AIV - Air Injection Valve
- AMGV - Air Management Valve
- AMS - Air Management System
- ANTBV - Anti-Backfire valve
- APDV - Air Pump Diverter Valve
- API - American Petroleum Institute
- AS - Airflow Sensor
- ASC - Automatic Stability Control
- ASE - Automotive Service Excellence
- ASIA - Automotive Service Industry Association
- ASME - American Society of Mechanical Engineers
- ASRV - Air Switching Relief Valve
- ASS - Air Switching Solenoid
- ASV - Air Switching Valve
- ATA - American Trucking Association
- ATF - Automatic transmission fluid
- ATS - Air Temperature Sensor
- AWD - All-wheel-drive
- B -
- BBDC - Before Bottom Dead Center
- BCDD - Boost-Controlled Deceleration Device
- BCI - Battery Council International
- BDC - Bottom dead center
- Bhp - Brake horsepower
- BHS - Bi-Metal Heat Sensor
- BMAP - Barometric and Manifold Absolute Pressure sensor
- BP - Barometric Pressure sensor
- BPA - By-Pass Air solenoid
- BPEGR - Backpressure EGR
- BPS - Barometric Pressure Sensor
- BTU - British Thermal Unit
- BV - Bowl Vent port
- BVT - Backpressure Variable Transducer
- C -
- C-3 - Computer Command Control system
- C-4 - Computer Controlled Catalytic Converter system
- CAM - Choke Air Modulator switch
- CANP - Canister Purge solenoid
- CAS - Cleaner Air System
- CAT - Catalytic Converter
- CAV - Coasting Air Valve
- CBVV - Carburetor Bowl Vent Valve
- CC - Catalytic Converter
- CCC - Computer Command Control; Converter Clutch Control solenoid
- CCEGR - Coolant Controlled Exhaust Gas Recirculation
- CCEVS - Coolant Controlled Engine Vacuum Switch
- CCIE - Coolant Controlled Idle Enrichment
- CCO - Converter Clutch Override
- CCS - Controlled Combustion System
- CCT - Computer Controlled Timing
- CCV - Closed Crankcase Ventilation system
- CEC - Combined Emission Control system; Computerized Emission Control system; Combination Emission Control
- CES - Clutch Engine Switch
- CI - Cubic Inches
- CID - Cubic Inch Displacement
- CIS - Continuous Injection System
- CKV - Check Valve
- CLC - Converter Lock-up Clutch
- CO - Carbon Monoxide
- CO2 - Carbon Dioxide
- COC - Conventional Oxidation Catalyst
- CP - Crankshaft Position sensor
- CPRV - Canister Purge Regulator Valve
- CPS - Canister Purge Solenoid
- CPV - Canister Purge Valve
- CRV - Coasting Richener Valve
- CSOV - Canister purge Shut Off Valve
- CSSA - Cold Start Spark Advance system
- CSSH - Cold Start Spark Hold system
- CTAV - Cold Temperature Activated Vacuum
- CTO - Coolant Temperature Override switch
- CTS - Coolant Temperature Sensor; Coolant Temperature Switch
- CTVS - Choke Thermal Vacuum Switch
- CV - Check Valve
- CWM - Cold Weather Modulator
- D -
- DBC - Dual-Bed Catalytic Converter
- DC - Direct current
- DEFI - Digital Electronic Fuel Injection
- DFS - Deceleration Fuel Shut-off
- DIS - Distributorless Ignition System
- DLV - Delay Valve
- DP - Dashpot
- DPDT - A double-pole, double-throw switch
- DPST - A double-pole, single-throw switch
- DRB II - Diagnostic Readout Box II
- DS - Detonation Sensor See knock sensor
- DSAV - Deceleration Spark Advance system
- DV - Delay Valve
- DVOM - Digital Volt-Ohmmeter
- DVTRV - Diverter Valv
- E -
- ECA - Electronic Control Assembly
- ECC - Electronic Controlled Carburetor
- ECM - Electronic Control Module
- ECS - Evaporation Control System
- ECT - Engine Coolant Temperature sensor
- ECU - Electronic Control Unit
- EDIS - Electronic Distributorless Ignition System
- EDM - Electronic Distributor Modulator
- EEC - Evaporative Emission Controls
- EEC/EEC-I/EEC-II/EEC-III/EEC-IV - Electronic Engine Control systems
- EEGR - Electronic EGR valve
- EFC - Electronic Feedback Carburetor; Electronic Fuel Control
- EFE - Early Fuel Evaporation
- EFE TVS - EFE Thermal Vacuum Switch
- EFI - Electronic Fuel Injection
- EGO - Exhaust Gas Oxygen sensor
- EGR-EPV - EGR External Pressure Valve
- EGR-EVR - EGR Electronic Vacuum Regulator
- EGR-FDLV - EGR Forward Delay Valve
- EGR-RSR - EGR Reservoir
- EGR-S/O - EGR Shut-Off
- EGR-TVS - EGR Thermal Vacuum Switch
- EGRV - EGR Vent solenoid
- EGR-VCV - EGR Vacuum Control Valve
- EGR-VSOL - EGR Vacuum Solenoid
- EGR-VVA - EGR Venturi Vacuum Amplifier
- EHCV - Exhaust Heat Control Valve
- EIS - Electronic Ignition System
- ELB - Electronic Lean Burn
- EMF - Electromotive Force, or Electromagnetic Frequency
- EPA - Environmental Protection Agency
- EPC - Electronic Pressure Control
- EPR-SOL - Exhaust Pressure Regulator Solenoid
- EPR-VLV - Exhaust Pressure Regulator Valve
- ERS - Engine Rpm Sensor
- ESC - Electronic Spark Control system
- ESS - Engine Speed Sensor
- ESSM - Engine Speed Switch Module
- EST - Electronic Spark Timing system
- ETC - Electronic Throttle Control
- EVAP - Evaporative emission control system
- EVCR - Emission Vacuum Control Regulator
- EVP - EGR Valve Position sensor
- EVR - EGR Vacuum Regulator
- F -
- FAP - Forced Air Pre-heat system
- FBC - Feedback Carburetor system
- FBCA - Feedback Carburetor Actuator
- FCS - Feedback Carburetor Solenoid; Feedback Control System; Fuel Control Solenoid; Fuel Control System
- FCV - Fuel Cut-off Valve
- FI - Fuel Injection
- FVEC - Fuel Vapor Emission Control
- FVR - Fuel Vapor Recovery system
- H -
- HAC - High altitude compensator
- HAEC - High Altitude Emission Control system
- HAI - Heated Air Inlet system
- HC - Hydrocarbon
- HCV - Heat control valve
- HEGO - Heated EGO sensor
- HEI - High Energy Ignition
- HSC - High Swirl Combustion chamber
- I -
- IAC - Idle Air Control
- IAS - Inlet Air Solenoid Valve
- IAT - Intake Air Temperature
- IBP - Integral Back Pressure
- ICM - Ignition Control Module
- ID - Inside diameter
- IGN - Ignition
- IHP - Indicated Horsepower
- IMVC - Intake Manifold Vacuum Control
- INJ - Injector
- INJ GND - Injector Ground
- ISS - Idle Stop Solenoid
- ITC - Ignition Timing Control system
- ITS - Idle Tracking Switch
- IVV - Idle Vacuum Valve
- J -
- JAS - Jet Air Stream
- JCAV - Jet-Controlled Air Valve
- JVS - Jet Valve System
- K -
- KAM - Keep Alive Memory
- KNK - Knock Sensor
- KS - Knock Sensor
- M -
- MAF - Mass Air Flow Sensor
- MAJC - Main Air Jet Control
- MAT - Manifold Absolute Temperature Sensor
- MCS - Mixture Control System
- MCT - Manifold Charge Temperature Sensor
- MCU - Microprocessor Control Unit
- MEC - Motronic Engine Control
- MECS - Mazda Equipped Control System
- MEMA - Motor and Equipment Manufacturers Association
- MEWA - Motor and Equipment Wholesalers Association
- MFI - Mechanical Fuel Injection, or Multi-port Fuel Injection
- MHCV - Manifold Heat Control Valve
- MIL - Malfunction Indicator Light
- MPFI - Multi-Point Fuel Injection
- MTA - Managed Thermactor Air
- MVMA - Motor Vehicle Manufacturers Association
- N -
- NADA - National Automobile Dealers Association
- NAPA - National Automotive Parts Association
- O -
- OC - Oxidation Catalyst
- OHV - Overhead Valve
- OS - Oxygen sensor
- OSAC - Orifice Spark Advance Control
- OSHA - Occupational Safety and Health Administration
- OTVS - Oil Thermal Vacuum Switch
- OXS - Oxygen Sensor system
- P -
- PA - Pulse Air
- PACV - Pulse Air Check Valve
- PAF - Pulse Air Feeder
- PAI - Pulse Air Injection
- PAS - Pulse Air System
- PCOV - Purge Control Valve
- PCV - Positive Crankcase Ventilation system
- PCVS - PCV Solenoid
- PCVV - Positive Crankcase Ventilation Valve
- PECV - Power Enrichment Control Valve
- PFE - Pressure Feedback EGR sensor
- PFI - Port Fuel Injection
- PIP - Profile Ignition Pickup
- PROM - Programmable Read-Only Memory
- PSOV - Canister Purge Shut-Off Valve
- PSPS - Power Steering Pressure Switch
- PSV - Pulse Air Shut-off Valve
- PTC - Positive Temperature Coefficient choke heater
- PVA - Ported Vacuum Advance
- PVCS - Ported Vacuum Control System
- PVFFC - Pressure/Vacuum Fuel Filler Cap
- PVS - Ported Vacuum Switch
- R -
- RAM - Random Access Memory
- RC - Rear Catalytic Converter
- RDV - Retard Delay Valve or Reverse Delay Valve
- RMA - The Rubber Manufacturers Association
- ROM - Read Only Memory
- S -
- SAE - Society of Automotive Engineers
- SAS - Secondary Air Supply system See “Air Injection System.”
- SBC - Single Bed Catalytic converter; Small Block Chevy
- SCC - Spark Control Computer
- SCS - Spark Control System, or Speed Controlled Spark
- SCVAC - Speed Control Vacuum Control
- SDV - Spark Delay Valve
- SEC ACT - Secondary Actuator
- SEFI - Sequential Electronic Fuel Injection
- SFI - Sequential Fuel Injection
- SHED - Sealed Housing Evaporative Determination system
- SIL - Shift Indicator Light
- SIS - Solenoid Idle Stop
- SOL V - EGR Solenoid Vacuum Valve Assembly
- SPFI - Single-Point Fuel Injection
- SPDT - Single-Pole, Double-Throw Switch
- SPST - Single-Pole, Single-Throw Switch
- SRS - Supplemental Restraint System (airbag)
- SSI - Solid State Ignition system
- SVCBV - Solenoid Valve Carburetor Bowl Vent
- SVV - Solenoid Vent Valve
- T -
- TAC - Thermostatically Controlled Air Cleaner
- TAD - Thermactor Air Diverter Solenoid
- TAV - Temperature Activated Vacuum System
- TBI - Throttle Body Injection
- TPMS - Tire Pressure Monitor System
- TC - Throttle Closer
- TCAC - Thermostatic Controlled Air Cleaner System
- TCC - Transaxle Converter Clutch system
- TCS - Throttle Control System; Transmission Converter Switch; Transmission Controlled Spark
- TDC - Top Dead Center
- TDP - Throttle closing Dashpot
- TDS - Time Delay Solenoid
- TEC - Thermactor Exhaust Control system
- TES - Thermal Electric Switch
- TFI, TFI-IV - Thick Film Integrated Ignition (Ford systems)
- TIC - Thermal Ignition Control
- TIV - Thermactor Idle Vacuum valve
- TK - Throttle Kicker
- TKA - Throttle Kicker Actuator
- TKS - Throttle Kicker Solenoid
- TO - Thermal Override
- TOC - Throttle Opener Control system
- TP - Throttle Position; Throttle Position Sensor
- TPI - Tuned Port Injection
- TPS - Throttle Position Sensor
- TR - Thermal Reactor
- TSD - Throttle Solenoid
- TSP - Throttle Solenoid Positioner
- TVS - Temperature Vacuum Switch; Thermal Vacuum Switch
- TVSV - Thermostatic Vacuum Switch Valve
- TVV - Thermal Vacuum Valve; Thermal Vent Valve
- TWC - Three-Way Catalyst
- U -
- UBC - Underbody Catalyst
- V -
- VAC - Vacuum Advance Control
- VAF - Vane Air Flow meter
- VAT - Vane Air Temperature sensor
- VAV - Vacuum Advance Valve
- VB - Vacuum Break
- VBV - Vacuum Bias Valve
- VCKV - Vacuum Check Valve
- VCS - Vapor Control System; Vacuum Control Switch
- VCV - Vacuum Control Valve
- VDV - Vacuum Delay Valve; Vacuum Differential Valve
- VECI - Vehicle Emission Control Information Decal
- VHC - Vacuum Operated Exhaust Heat Control Valve
- VIN - Vehicle Identification Number
- VMV - Vacuum Modulator Valve
- VOC - Volatile Organic Compounds
- VOM - Volt-Ohmmeter
- VOTM - Vacuum-Operated Throttle Modulator
- VP - Vacuum Pump
- VRDV - Vacuum Retard Delay Valve
- VRESER - Vacuum Reservoir
- VREST - Vacuum Restrictor
- VR - Variable Reluctance Sensor
- VR/S - Vacuum Regulator Solenoid
- VRS - Variable Reluctance Sensor
- V-RSR - Vacuum Reservoir
- V-RST - Vacuum restrictor
- VRDV - Vacuum Retard Delay Valve
- VRES - Vacuum Reservoir
- VREST - Vacuum Restrictor
- VRV - Vacuum Reducer Valve; Vacuum Regulator Valve
- VS - Vacuum Switch
- VSA - Vacuum Switch Assembly
- VSC - Vehicle Speed Control Sensor
- VSS - Vehicle Speed Sensor; Vacuum Switch Solenoid
- VSV - Vacuum Solenoid Valve; Vacuum Switching Valve
- VTM - Vacuum Throttle Modulator
- VTP - Vacuum Throttle Positioner
- VTV - Vacuum Transmitting Valve
- VVA - Venturi Vacuum Amplifier
- VVC - Variable Voltage Choke
- VVT - Variable Valve Timing
- VVV - Vacuum Vent Valve
- W -
- WAC - Wide-Open Throttle Air Conditioner Cutoff
- WOT - Wide-Open Throttle
- WOTS - Wide-Open Throttle Switch
- WOTV - Wide Open Throttle Valve
