Abbreviations ABDC ABS ABS warning light Accelerator Accelerator pump Accident Accumulator(A/C) Accumulator(Brake) Accumulator piston Active sensor Active suspension system ACT Active suspension Actuator ADS Add-on trans cooler Additives Advance(Ignition timing) AEA AERA Air bag Air bleed Air cleaner Air-cooled Air conditioning Air conditioning technician Air control door Air dam Air filter Airflow meter Airflow sensor Air-fuel ratio Air gap Air horn Air injection system Air pollution Air spring ALDL Align Alignment heads Alignment technician Allen wrench Alloy Alpha numeric Alternating current (ac) Alternator Altitude compensator Aluminum Ambient temperature Ambient air temperature switch Ammeter Ampere Anaerobic sealer Analog Aneroid Annealing Anode Anti-dieseling solenoid Anti-lock brake system (AES) Anti-rattle clip Antifreeze Antifriction bearing Apprentice programs Apprentice Technician Arcing Armature ASE ASIA ASME Asbestos Aspect ratio Asphyxiation ATA ATDC Atmospheric pressure Atom Atomizes Automatic level control system Automatic transmission Automatic trans fluid (ATF) Auxiliary oil cooler AWO Axle Axle housing Axle ratio Backfire Backlash Backing plate Back pressure Backup lights Battle Ball bearing (Antifriction) Ball joint Ballast resistor Band Band and clutch application chart Barometric pressure sensor Base brakes Battery Battery cables Battery capacity Battery charging Battery plate Battery rating Battery temperature sensor Battery voltage BBDC BCI DOC Bead Bearing Bell housing Bendix drive Bezel Bias tire Bias-belted tire Bleed Blend door Block Block heater Blowby Blower motor Blueprinting Body computer module (BCM) Body technician Boost pressure Bore Boring bar Boss Bottled gas Bourdon tube Bowl vent Brake anchor Brake booster Brake drum Brake fade Brake feel Brake fluid Brake horsepower (BHP) Brake hoses Brake lines Brake shoes Brake technician Brake System Warning Light Braking ratio Braze Break-in Breaker arm Breaker points Broach Bronze Brown and Sharpe (B & S) Gage Brushes British thermal unit (BTU) BTDC Burnish Bus Bushing Butane Bypass Bypass valve CAFE Calibrate Caliper Calipers Calorie Cam angle Cam ground piston Cam lobe Camber Camshaft Camshaft gear Camshaft position sensor Capacitance Carbon (C) Carbon dioxide (COJ Carbon monoxide (CO) Carbon tracking Carburetor Carburetor circuits Carburetor icing Carcinogen Cardan universal joint Case-harden Castellated nut Caster Catalytic converter Cathode Cell Celsius Center link Center of gravity Center support bearing Central processing unit (CPU) Centrifugal advance mechanism Centrifugal force Cetane number CFM Chamfer Change of state Charcoal canister Charge Charging station Chase Chassis Chassis dynamometer Chatter Check engine light Check valve Chilled iron Choke plate Choke stove Chromium Circuit Circuit breaker Clearance Clockwise Closed cooling system Closed loop Cluster gear Clutch Clutch disc Clutch fork Clutch housing Clutch linkage Clutch pilot bearing Clutch start switch Coefficient of friction Coil Coil spring Coil spring pressure plate Cold cranking amps Cold patching Cold solder Cold start valve Combination valve Combustion Combustion chamber Commutator Compensating port Composite headlamp Compound Compression Compression gauge Compression ignition Compression ratio Compression rings Compression stroke Compressor Compressor wheel Condense Condenser Conduction Conductor Connecting rod Connecting rod bearing Connecting rod cap Constant mesh gears Constant velocity axle Constant velocity universal joint Contact pattern Continuous fuel injection Contraction Control arm Control module Control rack Control valve Convection Coolant Coolant nozzles Coolant recovery system Coolant temperature sensor (CTS) Cooling fins Cooling system Core hole plugs Corrosion inhibitors Cotter pin Counter shaft Counterbalance shaft Counterclockwise rotation Countersink Cradle Crankcase Crankcase dilution Crankshaft Crankshaft gear Crankshaft position sensor Crankshaft throw Cross and roller Crossmember CRT Cu. In. Curb weight Current CVT Cycle Cylinder Cylinder head Damper Dashboard Dashpot Dead axle Dead center (DC) Deceleration Deflection rate Deglazer Degree Degree wheel Density Deploy Desiccant Detergent oil Detonation Dexron III/Mercon Diagnosis Diagnostic control module Diagnostic trouble codes Diagonally split brake system Dial gauge Diaphragm Die Diesel engine Diesel injection pump Dieseling Differential Differential case Differential yoke Digital EGR valve Digital signal Dimmer switch Diode Dipstick Direct current (de) Direct drive Direct fuel injection Direct ignition system Disc brake assembly Discharge Discharging (air conditioning) Displacement Distillation Distribution tubes Distributor Distributor cap Distributor injection pump Distributor rotor Distributorless ignition system Diverter valve Documentation Dog tracking DOHC Double lap flare Dowel pin Draw Draw-filing Driveability technician Drive-fit Driveline Drive shaft Drive shaft angle Drive shaft imbalance Drive train Driveability Drop center Drum brake assembly Dry charged battery Dry friction Dual exhaust system Dust cap Dwell Dye penetrant Dynamic balance Dynamic imbalance Dynamometer ECC Eccentric ECM Economizer valve EEC EFE ELC Electrical technician Electrode Electrolyte Electromagnet Electromagnetic interference (EMI) Electromotive force (EM F) Electron Electron theory Electronic control unit (ECU) EEPROM Element Elliot axle Emissions Emissions information label Emissions tune-up End play Energy Engine Engine displacement Engine dynamometer Engine mounts Engine speed sensor EPA Equalizer pipe EPROM ESC EST Estimate Ester oil Ethyl alcohol Ethylene glycol Evacuation (air conditioning) Evaporation Evaporation control system Evaporator Exhaust back pressure Exhaust gas analyzer Exhaust gas recirculation (EGR) Exhaust manifold Exhaust pipe Exhaust stroke Exhaust system Expansion tank Expansion valve Extension housing Extreme pressure lubricants (EP) F-head Fahrenheit Fan Fan clutch Fast idle cam Feathering Feeler gauge Ferrous metal Fiber optic Field Filter Final drive ratio Firewall Firing order Fit Flange Flare Flash point Flashover Float Float bowl Float circuit Float level Flooding Flux Flywheel Foot-pound (ft.-lb.) Force Foundation brakes Four-gas analyzer Four-stroke cycle engine Four-wheel alignment Four-wheel drive Four-wheel steering Frame Frame rails Free electrons Freeze plugs Freezing point Frequency Friction Friction bearing Front end technician Fuel Fuel bowl Fuel distributor Fuel injection Fuel injector Fuel lines Fuel pulsation Fuel pump Fuel rail Fuel tank Fulcrum Full-floating axle Full-flow filter system Full-time transfer case Full pressure system Full throttle cut-out switch Fuse Fusible link Galvanize Galvanometer Gas Gas line freeze Gasahol Gasket Gasoline Gassing Gear Gear backlash Gear clash Gear oil Gear pump Gear ratio Gear reduction Gearbox ratio Generator Glass pack muffler Glaze Glaze breaker Glow plugs Governor GPM Grade markings Gram (G) Grid Grind Groove Gross axle weight rating (GAWA) Gross horsepower Gross torque Gross vehicle weight rating (GVWR) Ground Growler Gum Gut Hall effect switch Halogen bulb Harmonic balancer Harmonic vibration Hazard flashers Hazardous waste Header Headlights Headlight delay switch Heat exchanger Heat range Heat riser Heat-shrink tubing Heat shield Heat stove Heat treatment Heater core Heavy repair technician Heel Height sensing proportioning valve Height sensor Helical gear Helicoil Hemispherical combustion chamber Herringbone gear High side Hone Hood pins Horizontal-opposed engine Horn Horsepower (hp) Hose Hose clamp Hot idle compensator Hot tank Hotchkiss drive Hub Hydraulics Hydraulic modulator Hydraulic power booster Hydraulic system Hydraulic valve lifters Hydrocarbons (HC) Hydrometer Hygroscopic Hypoid gearing I-head ID Idle air control valve (IAC) Idle mixture adjustment screw Idle speed Idle speed-up solenoid Idler arm Ignition Ignition coil Ignition module Ignition switch Ignition timing Impact sensor Impeller LLClined engine LLCluded angle LLComing air temperature sensor Independent suspension Indicated horsepower (IHP) Indirect fuel injection Induction Inertia Inertia switch Inflation pressure Information center Infrared rays Inhibitor Injector Inline Inline engine Input sensors Input shaft Insulation Intake air heaters Intake manifold Intake stroke Intake valve Integral Integrated circuit (IC) Intermediate gear Intermittent Intermittent codes Internal combustion engine Internal gear Ion Ionize Jet Joule Jounce bumper Journal Jump start Jumper cables Jumper wire Keep alive memory (KAM) Key Keyway Kickdown valve Kilometer (kin) Kinetic energy Kingpin Knock Knock sensor Knurl L-head engine Lacquer Laminate Land Lapping Latent heat Lateral runout Lathe Lead burning Leaf spring Leak detector Lean mixture LED code Lever Lift Light emitting diode (LED) Light repair technician Limited-slip differential Liner Linkage Liquid Liquid withdrawal Liter Live axle Load range Lock washer Locking hub Lockup torque converter Longitudinal Louver Low brake pedal Low fluid warning switch Low pressure switch Low side Lug bolts Lug nuts MacPherson strut suspension Magnetic clutch Magnetic field Magnetic timing meter Magnetism Main bearing Main body Main cap Main discharge tube Maintenance-free battery Maintenance tune-up Malfunction indicator light (MIL) Manifold Manifold absolute pressure sensor Manifold air temperature sensor Manifold heat control valve Manifold vacuum Manual transmission/transaxle Mass airflow sensor (MAF) Master cylinder Master Technician Material Safety Data Sheet (MSDS) Mailer Mechanical efficiency Mechanical fuel injection Mechanical fuel pump Mechanical lifter Melting point Meter Metering rod Metering valve Methanol Metric system Micrometer Microprocessor Millimeter (mm) Milling Mineral oil Misfiring Mixture control (MC) solenoid Modulator Molecule Monoblock Motor MPH Muffler Multi-viscosity oil Multimeter Multiple disc clutch Multiplexing Multiport fuel injection MVMA NADA Natural gas NC threads Needle bearing Needle valve Negative terminal Net horsepower Net torque Neutral safety switch Neutron Newton meter (N*m) NF thread NHTSA Nonferrous metal North pole Nozzle NSC Nut lock OBD II Octane OD Odometer OEM Ohm Ohm’s Law Ohmmeter Oil classification diesel Oil classification gasoline Oil cooler Oil gallery Oil pickup Oil pressure gauge Oil pump Oil ring Oil seal Oil slinger Open circuit Open loop Optical sensor Orifice Orifice tube Oscillate Oscilloscope Otto cycle Out-of-round Output device Output shaft Overdrive Overflow tank Overhead camshaft (OHC) Overhead valves (OHV) Overrunning clutch Oversteer Oxides of nitrogen (NOx) Oxydize Oxidizing catalyst Oxygen sensor (02S) Packing Pad Pan Pancake Engine Parallel circuit Parallelogram steering linkage Parasitic load Parking brakes Parking lights Pad-time transfer case Pascal’s Law Pawl Peen Penetrating oil Permanent magnet Petcock Petroleum Phillips head screw Phosgene gas Phosphor-bronze Photo sensitive diode Pickup coil Pilot bearing Pilot shaft Pinging Pinion carrier Pinion gear Piston Piston boss Piston collapse Piston displacement Piston expansion Piston head Piston lands Piston pin Piston rings Piston ring end gap Piston ring grooves Piston skirt Piston skirt expander Pitman arm Pivot lever Planet carrier Planetary gears Plastigage Plates Platinum (Pt) Play Plies Plug gap Plug heat range POA Polarity Pole Piece Pole shoes Polyalkylene glycol (PAG) oil Polymer Poppet valve Port fuel injection Positive crankcase ventilation (PCV) Positive Potential horsepower Potentiometer Power booster Power brakes Power steering Power steering pump Power stroke Powertrain Power valve PPM Practical efficiency Preheating Preignition Preloading Press-fit Pressure Pressure bleeding Pressure cap Pressure differential switch Pressure plate Pressure plate cover Pressure regulator Pressure relief valve Pressure sensor Pressure-splash system Pressure-temperature relationship Primary brake shoe Primary circuit Primary winding Primary wiring Printed circuit Programmable read only memory Prony brake Propane Propeller shaft Proportioning valve Proton PSI Pulsation damper Pulse air injection system Pulse fuel injection Pulse width Pump Purge Push rod Quadrant Quenching Quick charge test R-12 (CFC-12) R-134a (HFC-134a) Rack Rack-and-pinion Radial Radial compressor Radial runout Radial tire construction Radial tire pull Radiation Radiator Radiator core Radius Radius rods Random access memory (RAM) Ram air Rated horsepower Ratio Read only memory (ROM) Ream Rear wheel shim Receiver-dehydrator Reciprocating motion Re-circulating ball worm and nut Rectified Reduction gear Reed switch Reference voltage Refrigerant Refrigerant hose Refrigerant line Refrigerant oil Refrigerant recovery unit Relative volatility Relay Relieve Reluctor Remote keyless entry Removable carrier Reserve capacity Reservoir Resistor Resistance Resonator Retard Retread Retrofitting Return spring Reverse bias Reverse elliot axle Reverse flow muffler Reverse flush Reverse idler shaft Rheostat Ribbed belt Rich mixture Ridge reamer Rim Ring expander Ring gap Ring gear Rivet RMA Road crown Road feel Rocker arm Rocker shaft Rod cap Roller bearing Roller clutch Roller lifter Roller vane pump Rollover valve Room temperature vulcanizing Rotary engine Rotary motion Rotary pump Rotary valve Rotor (Brake) Rotor (Ignition) Rotor housing Rotor pump RPM Running-fit Run-on Runout Rzeppa joint SAE SAE thread Safety rim Safety valve Safety washer Scale Saybolt test Scanner Scatter shield Scavenging Schrader valve Score SCR Screw extractor SCS Scuffing Seal Sealant Sealed beam headlight Sealed bearing Seat Secondary Secondary brake shoe Secondary wires Secondary circuit Secondary winding Section height Section width Sector shaft Sediment Seize Self-adjusting brakes Self-diagnostics Self-energizing brakes Self-induction Self test SEMA Semi-metallic Semiconductor Semielliptical leaf spring Sensible heat Sensor Separator Series circuit Series-parallel circuit Serpentine belt Service engine soon (SES) light Service valves Servo Servo action Setback Shackle Shift forks Shift lever Shin linkage Shift point Shim Shimmy Shock absorber Short circuit Shrink fit Shroud Shunt Shunt winding Sidedraft Sidewall Sight glass Silicon (Si) Single barrel Single exhaust system Skid plate Slant engine Slave cylinder Sleeve Sliding gear Slip angle Slip rings Slip yoke Sludge Smog Snap ring Sodium valve SOHC Solenoid Solid axle Solid axle suspension Solid state Solvent South pole Spacer Space saver spare tire Spark Spark advance Spark gap Spark ignition Spark knock Spark plug Spark plug wires Specific gravity Speedometer Speed control Speed density Speed rating Spider gears Spindle Spiral bevel gears Splash system Splines Split hydraulic system Spool valve Sprag clutch Spring Spring booster Spring loaded Spring oscillation Spring pressure Spring steel Sprung weight Spur gear Spud hole Sq.ft. Sq.in. Squirrel cage Squish area Stabilizer bar Staked nut Stall Stall speed Stall test Stamped steel Starter Starter pinion gear Static balance Static imbalance Static electricity Stator Steel pack muffler Steering arm Steering axis LLClination (SAI) Steering column Steering gear Steering geometry Steering knuckle Steering linkage Steering shaft Stoichiometric Stoplight Straight roller bearing Stroke Strut Strut damper cartridge Stud STV Sulfated Sump Sun gear Supercharger Supplemental restraint systems Suspension system Sway bar Sweating Switch Synchronizer assembly T-head Tachometer Tailpipe Tandem booster Tank gauge unit Tap Taper Tapered roller bearing Tappet TCS TDC Technical service bulletins (TSR) Temperature gauge Tension Terminals Test light Thermal efficiency Thermistor Thermostat Thermostatic air cleaner Thermostatic compressor switch Thermostatic expansion valve (TVX) Throttle body fuel injection (TBI) Throttle body Throttle plate Throttle position sensor (TPS) Throttle return dashpot Throttle valve Throw Throw-out bearing Thrust angle Thrust bearing Thrust load Thrust washer Tie rod Timing belt Timing chain Timing gear cover Timing light Timing marks Timing sprocket Tire Tire rating Toe Toe-out on turns Tolerance Torque Torque converter Torque multiplication Torque stick Torque wrench Torsen differential Torsion bar Tracking Traction Traction control system (TCS) Tramp Transducer Transfer case Transistor Transaxle Transmission Transmission control solenoid Transmission oil cooler Transmission/transaxle technician Tripod CV-joint Troubleshooting chart Trunnions Tune-up Turbine wheel Turbocharger Turbulence Turning radius Two-stroke cycle engine Two-wheel alignment UAW UIC Undercoating Understeer Unibody Uniform Tire Quality Grading System Universal joint Unleaded gas Unsprung weight Upset Upshift V-Belt V-Engine Vacuum Vacuum advance Vacuum booster Vacuum gauge Vacuum modulated EGR Vacuum motor Vacuum pump Vacuum reservoir Vacuum runout point Vacuum switch Valve Valve clearance Valve core Valve duration Valve face Valve float Valve guide Valve head Valve keeper (or key) Valve lash Valve lift Valve lifter Valve margin Valve overlap Valve ports Valve seal Valve seat Valve spring Valve spring seat Valve spring shim Valve stem Valve timing Valve train Vane pump Vapor lock Vaporize Variable displacement compressor Vehicle identification number (VIN) Vehicle speed sensor (VSS) Venturi Venturi vacuum Vibration damper Viscosimeter Viscosity Viscosity index Viscous coupling Volatility Volt Voltage drop Voltage regulator Voltmeter Volume Volumetric efficiency Vortex Vulcanization Wandering Wankel engine Waste gate Waste spark Water detector Water jacket Water pump Wall Wear bar Wedge Wedge chamber Wet compression test Wet friction Wet sleeve Wheel alignment Wheel balancer Wheelbase Wheel bearing Wheel cover Wheel cylinder Wheel hop Wheel rim locks Wheel speed sensor Wheel shimmy Wheel tracking Wheel tramp Wheel weight Windup Wide open throttle switch Wire harness Wiring diagram Work Worm gear Worm and roller Worm and sector WOT Wrist pin Zener diode        Letters or letter combinations that stand for words. Used extensively in the automotive industry.