Glossary of Automotive Terms – A

• Also called earthmover, off-road, or off-the-road tire.

• The sides of the two legs of the A-arm are connected to the chassis by rubber bushings and the peak of the A-arm is attached to the wheel assembly.
• In this way, the wheel can freely move up and down.
• Sometimes there is an upper A-arm, a lower A-arm, or both upper and lower A-arms.
• The British call it a wishbone.

1. The act of a transporting company (bus, courier, railway, ship, etc.) in which it will no longer service a previously serviced route. In some cases abandonment must be approved by the ICC
2. The act of a shipper or consignee who refuses to accept delivery
3. The act of relinquishing title to damaged or lost property by claiming a total loss.

• The AB designation is made because it has a pointed end similar to a type-A screw and thread dimensions similar to a type-B screw.

1. Abbreviation for Aerial Bunched Conductors
2. Abbreviation for Automatic Beam Control.

• A system for classifying inventory or parts within a warehouse where fast moving products are designated as ‘A’ items, while ‘B’ and ‘C’ items are not as fast moving.
• In some warehouses, however, ‘A’ items are those with the best profit margins.

• A term used in timing the relation of the spark and the crankshaft
• measured in degrees of rotation.

• Opposite to adhere

• e.g., Teflon® on frying pans does not allow eggs to stick to its surface.
• Opposite of adhesive

1. A hard grit used for sanding or grinding.
   • Usually a powder e.g., silicon carbide powder.
2. Materials such as sand or chipped rock that are spread on paved roads to increase vehicle traction.
   • Also called aggregates

• In order to clean steel or remove rust from iron or scale from metal, sand or some other powder substance is forced by air pressure through a nozzle.
• In this way the small particles of abrasive can penetrate the metal where sanding with sandpaper cannot.
• Also, very small craters are formed on the surface of the metal from the blasting action.
• When thoroughly cleaned the metal is ready for painting.
• Paint adheres better to these craters and imperfections than to a perfectly smooth surface.

• It is used to remove the grime and oils from a surface or from your hands.

• The Abbreviation ABS comes from the German Anti Blockier System.
• A computer, sensors, and solenoid valves work together to sense wheel speed in order to modulate braking force if wheels lockup during braking.
• ABS can help the driver retain control of the vehicle during heavy braking on slippery roads.
• It works on the principle of braking a wheel until it just begins to skid (this is the point where braking efficiency would drop off dramatically) and then releasing the brake pressure and re-applying the brakes.
• Wheel speed sensors identify the skid point and trigger a release in brake pressure.
• The cycle is repeated many times a second.
• The driver will feel a rapid pulsing at the brake pedal and hear a chattering noise as ABS is applied.

1. Pressure measured from a starting point of zero in perfect vacuum.
   • When measured by the absolute pressure scale, atmospheric pressure is 14.7 psi or 29.92 inches of mercury (in-Hg).
2. Total pressure equal to gauge pressure plus 14.7 lbs./sq. in. at sea level.

• The temperature plus 273°C.

1. The use of a chemical or filter to remove unwanted particles or characteristics from something.
2. When light strikes a surface, some of it penetrates into the material and is trapped. This trapped energy is called absorption. Transformation into other forms suffered by radiant energy passing through a material substance.

1. The volume of gas, measured at STP, dissolved by unit volume of a liquid under normal pressure (i.e., one atmosphere).
2. The fraction of the energy which is absorbed.

1. A part which stops the motion of another part from proceeding any farther.
2. The contact made between opposing teeth of two gears.
3. The structure that supports the end of a bridge.

1. An abbreviation for across corners
   • Indicates the distance on a nut or bolt head from one corner to the opposite corner rather than the distance from one flat surface (A/F) to the opposite.
   • The A/F measurement determines the size of wrench needed to install or remove the nut or bolt.
   • The A/C measurement determines the size of hole needed to insert a recessed nut or bolt head.
2. Abbreviation for alternating current.
3. Abbreviation for air conditioning or air conditioner.
   • Sometimes spelled ‘A/C’ or ‘A.C.’
4. Symbol for actinium
5. The transformation temperature on heating of the phase changes of iron or steel, subscripts indicating the designated change, e.g., Ac1 is the eutectoid (723°C) and Ac3 the ferrite/austenite phase boundary.
6. Abbreviation for Asphaltic concrete.
   • A mixture of asphalt cement, graded aggregate, mineral filler, and additives.

• Pronounced ah-SEEK-uh
• The 1955-61 Aceca models are milestone cars.

1. Abbreviation for Automatic Cruise Control.
2. A term found on a cruise control switch which indicates the direction the switch needs to be moved to increase the speed (accelerate) of the vehicle.
3. Abbreviation for Air Conditioning Clutch
4. Abbreviation for Automatic Climate Control

1. To increase the speed of a vehicle. Opposite of decelerate.
2. To increase the speed of a chemical reaction
   • To speed up the chemical reaction or curing process of an adhesive.
   • For example, you can speed up the drying time of an adhesive or sealer by increasing the temperature or by adding a chemical curing agent, or accelerator, to a base compound.

• Velocity is steady and is measured in distance per time (e.g., feet per second, miles per hour, kilometres per hour).
• Acceleration keeps increasing and is measured in velocity per time (e.g., feet (or metres) per second per second or feet (or metres) per second squared).
• It is a vector quantity and has both magnitude and direction.
• It may be positive or negative depending upon whether the object is speeding up or slowing down.
• According to Newton’s second law of motion, acceleration is equal to the force, divided by mass (A=F/M).
• The latter is often called deceleration.

• The degree of tolerance depends on the magnitude and duration of the acceleration as well as the direction of the force against his body.

1. In automobiles, this is the gas pedal which is attached by linkage to the throttle in the carburetor or to the fuel injection system.
   • It regulates the amount of fuel which is sent to the engine.
   • In motorcycles, the accelerator is located on the right-hand twist grip or an actuating lever.
   • Also called throttle linkage.

   See

   • Depress the accelerator
   • Ease up on the accelerator
   • Step on the accelerator
   • Take foot off the accelerator
2. A chemical which is added to something to make a process happen more quickly.
   • For example, a chemical may be added to paint to cause it to dry faster.
   • The opposite is retarder.
   • A material added to an adhesive to speed up its cure or to chemically convert the whole mass to a solid.
   • Accelerators differ from catalysts in that they are a part of the chemical reaction and lose their chemical identity as a result.
3. Any substance increasing the speed of the vulcanization process of rubber.

• A small cylinder and piston usually located inside the carburetor that sprays an extra amount of fuel into the engine during acceleration.
• It improves acceleration by giving more boost and reducing a momentary lag in power.
• It is actuated by fully depressing the throttle pedal.

1. The act of receiving and signing for a shipment by the consignee which terminates the carrier’s contract and obligation.
2. A consignee’s promise to pay the shipping costs by signing and dating the bill for the goods and acknowledging any indebtedness to the company who shipped the goods.

• Unlike a crew cab (which has four full size doors) it has a half-door that can be opened only after the main door is opened.
• The seating is usually a little more cramped than in a crew cab.
• Other manufacturers call it
  • Club Cab
  • Extended Cab
  • King Cab
  • Xtracab
  • Supercab
  • Cab Plus

• It is usually covered with a removable panel for aesthetic or safety reasons to hide wiring, hoses, etc.

1. The cover which conceals the engine on a mid-engine vehicle.
   • Also called engine cover
2. A decorative plate which covers an access hole

• Also called a haul road

1. A storage battery for an electric car.
2. A part of a hydraulic system filled with nitrogen gas and used to store high pressure fluid to provide pressure assistance for system operation.
3. A pressurized container for an automatic leveling suspension system.
4. A part of the hydraulic system which is charged by the fluid pump, absorbs fluctuating fluid delivery, stores fluid at pressure, and can provide a rapid flow of fluid under pressure.
5. A device in the fuel line between the pump and filter that keep up the fuel pressure when the fuel pump is off thus preventing vapor lock and excessive fuel pump noise in having to build up pressure when needed
6. A vessel that stores hydraulic fluid under pressure.
7. A storage tank which receives liquid refrigerant from the evaporator and prevents it from flowing into the suction line before vaporizing.
8. A refrigerant storage device used on General Motors and Ford systems that receives vapor and liquid refrigerant from the evaporator.
   • The accumulator, which contains desiccant, performs a function similar to that of a receiver-drier it separates liquid from the vapor, retains the liquid and releases the vapor to the compressor.
   • Always located on the low side of the system.

• It is made up of a tank, filter, drying agent, and a vapor return tube.
• It is usually found on the evaporator outlet.
• It stores the excess refrigerant and removes the moisture from the refrigerant (thus the name drier).

• When burned in an atmosphere of oxygen, it produces one of the highest flame temperatures obtainable for welding.

• Used to store and ship acetylene.
• Also called acetylene tank or acetylene bottle

• It is made of fabric and rubber.

1. An electromagnetic generator for producing alternating EMF and delivering AC to an outside circuit.
2. A generator produces direct current (DC) while an alternator produces alternating current (AC).
   • Because alternators were introduced to automobile electrical systems after generators had been in use for some time, some people referred to the new alternator as AC generator.

• The constituents vary in nature and may or may not markedly influence the behavior of the oil.

• The ferrous sulfate can further react to form ferric hydroxide, or yellowboy, a yellow-orange iron precipitate found in streams and rivers polluted by acid mine drainage.

1. When the smoke created by factories and vehicle exhausts is taken by the wind and joined with rain clouds, the mixture is often acidic.
   • As a result the rain that falls to the ground (and even on your car) may damage whatever it strikes.
2. A form of wet deposition in which acid molecules or particles in the atmosphere are returned to the surface having been washed out by rain or snow as it falls.
   • The unnatural acidity (pH 3-5.5) is caused mainly by the oxides of sulfur and nitrogen from the burning of coal and oil.
3. Precipitation containing harmful amounts of nitric and sulfuric acids formed primarily by sulfur dioxide and nitrogen oxides released into the atmosphere when fossil fuels are burned.
   • It can be wet precipitation (rain, snow, or fog) or dry precipitation (absorbed gaseous and particulate matter, aerosol particles or dust).
   • Acid rain has a pH below 5.6.
   • Normal rain has a pH of about 5.6, which is slightly acidic.
   • The term pH is a measure of acidity or alkalinity and ranges from 0 to 14.
   • A pH measurement of 7 is regarded as neutral.
   • Measurements below 7 indicate increased acidity, while those above indicate increased alkalinity.
   • Also called acid precipitation or acid deposition

1. A double-pivoting steering system where the outer ends of the steering arms are bent slightly inward so that when the vehicle is making a turn, the inside wheel will turn more sharply than the outer wheel.
   • This is done to compensate for the greater distance the outside wheel must travel.
   • Notice 20 degrees on left wheel and 30 degrees on right wheel
2. Arrangement whereby a line extended from the track-arms, when the wheels are set straight ahead, should meet on the chassis centerline at 2/3 of the wheelbase from the front, allowing the inner stub-axle to move through a greater angle than the outer.

• The cutting portion resembles an acorn.

• Provides sealing for projecting threaded parts.

1. The science of sound waves including production and propagation properties.
2. The characteristics of the interior of a car which determine the quality of sound transmission inside.

• On a shorter term lease, the acquisition fee can have a large impact on the cost of the lease.

• The purpose of the A/C dimension is to know how large a hole might be needed to insert a recessed nut.

• The ends are sealed to keep tubing clean and dry.

• It is used for adhesives, protective coatings, and paint finishes.

1. Abbreviation for active control system
2. Abbreviation for air conditioning system
3. Abbreviation for attitude control system

1. Abbreviation for air charge temperature.
2. Abbreviation for active control technology

• It is used as a drier or desiccant

• When the engine is running, hot air is forced into the filter and push out the vapors into the engine.
• In this way, pollution is reduced and conservation of the fuel is maintained.
• Also called activated charcoal trap or charcoal canister.

• Also called an activator

• Also called activating agent.

• This is similar to chemical reactions where the reacting species must overcome an activation barrier.
• For fuel cells, this region is characterized by a drop from the theoretical EMF or ideal voltage prior to electron or ion flow.

• The active area is typically less than the total area of a cell to accommodate cooling, distribution, and sealing mechanisms.

• Also known as real power.

• Passive safety involves seat belts, airbags, bumpers, etc. so that in the event of an accident the passengers are protected.
• Active safety involves factors which will assist the driver in avoiding an accident.
• They include brakes, steering, handling response, acceleration, etc.

• These actuators place the wheels of the vehicle in the best position to accommodate rough roads as well as compensate for different load levels.

• It has no moving parts and is very efficient.

1. A device which controls or operates another device.
2. A regulating valve which converts a form of energy into mechanical motion to open or close the valve seats
3. A device which responds to an output signal from a computer.
4. The portion of a regulating valve which converts mechanical fluid, thermal energy, or electrical energy into mechanical motion to open or close the valve seats
5. An electrical mechanism for moving or controlling something indirectly instead of by hand, such as a door lock. The output device that the PCM controls such as solenoids, relays, fuel injectors and stepper motors.

• Also called diaphragm link.

• CL (1997-2003)
• Integra (1988-2001)
• Legend (1988-95)
• MDX (2001-07)
• NSX (1991-2005)
• RDX (2007-2009)
• RL (1996-2008)
• RSX (2002-06)
• SLX (1996-99)
• TL (1995-2008)
• TSX (2004-08)
• Vigor (1992-94)

1. Abbreviation for actual cash value
2. Abbreviation for air control valve
3. Abbreviation for air cushion vehicle (i.e., hovercraft).

1. A device used to connect two different types or sizes of electrical terminals
2. A connector which links two items usually of dissimilar structure or size.
3. A bracket on disc brakes on which the caliper mounts, or slides or floats.
   • Bolted to the spindle or steering knuckle, or the rear axle or control arm.

1. A control device which learns from repeated input so that under particular circumstances the control gives the learned response.
2. The ability of a control unit to adapt its closed-loop operation to changing operating conditions, such as engine wear, fuel quality or altitude, to maintain proper air-fuel mixture control, ignition timing or idle rpm. Also referred to as self-learning

• Opposite to abhere

1. Each surface that is to stick to another
2. A material which is stuck together by an adhesive.

1. The force which causes two surfaces to stick together
2. The sticking together of surfaces in contact with each other
3. The bonding of materials with adhesives (glues, cements, binders, etc), in which the intermolecular forces between adhesive and adherend provide the bonds.
4. The sticking together of two metals as a result of compressing them together
5. The sticking together of two dissimilar metals because of electrical transference of electrons.
6. The ability of paint, Primer, or glue to stick to the surface to which it is applied.
7. The ability of a tire to grip the surface of the road.
8. Mutual forces between two magnetic bodies linked by magnetic flux, or between two charged non-conducting bodies which keeps them in contact
9. Intermolecular forces which hold matter together, particularly closely contiguous surfaces of neighboring media, e.g., liquid in contact with a solid.

1. A substance (like glue) that is used to join two substances.
   • An adhesive must bond both mating surfaces through specific adhesion (molecular attraction), through mechanical anchoring (by flowing into holes in porous surfaces), or through fusion (partial solution of both surfaces in the adhesive or its solvent vehicle).
   • Various descriptive adjectives are used with the term adhesive to indicate types, such as

     a. physical form

     Liquid adhesive, film adhesive, etc.

     b. composition

     Resin adhesive, rubber adhesive, silicone based, mastic, etc.

     c. end use

     Metal-to-metal adhesive, plastic adhesive, rubber adhesive

     d. application

     Sprayable adhesive, hot melt adhesive, etc.

2. Agent for joining materials by adhesion, usually polymeric material.
   • May be based on thermoplastic resin (e.g., polystyrene cement) or thermoset (e.g., epoxy resin).
   • Viscosity is important for gap filling (high, as in epoxies) or surface penetration (low, as in cyano-acrylates).
   • Also called binder, cement, or glue

• Also describes a class of adhesives provided in dry film form with or without reinforcing fabric and which are cured by means of heat and pressure

• It usually comes in a roll of various widths.
• Sometimes used to insulate electrical wires (e.g., electrical tape) or to wrap a larger object (e.g., duct tape).
• Often the non-sticky side is shiny (but not always) to distinguish it from the sticky side.

• It comes in strips and is applied to a wheel rim to balance the wheel.
• Also called tape weight.

• It does not gain any heat or lose it

• In this way the engine is warm enough for efficient running and it does not overheat.

• It may involve one component (e.g., He adjusted the gasket to fit properly.) or a series of components (e.g., He adjusted the poor idle — might mean he set the ignition timing, adjusted the carburetor screws, changed the choke setting, cleaned or replaced the spark plugs, etc.)

• It has two bearing cups on either side.
• One cup is fixed in place while the other is removable or adjustable.
• This is the older type of bottom bracket before sealed cartridge bottom brackets became prevalent.
• The adjustable bottom bracket requires fixed and adjustable cup tools to properly tension the bearings.
• The bearings are not sealed, but they are easily accessible for cleaning and lubrication.

• Some emissions-era Rochester carburetors have a separate air passage to bleed air past an adjustment screw into the idle system.
• This screw is preset by the factory to produce precise off-idle air/fuel mixture ratios to meet emission-control requirements.

• The APT can be adjusted to control part-throttle mixtures more accurately than a fixed orifice.
• The APT detours around the main jet, going directly from the float bowl to the discharge nozzle feed well.

Click to supersize
Adjustable shock absorber

A type of shock absorber which can compensate for varying needs of stiffness or softness.

• Manual types (especially on motorcycles) require that you physically make the adjustment from one level to another by rotating securing rings.
• Automatic types are controlled by a computer as it senses particular changes in road condition.

• Polyphase motors
• motor oversizing
• motor rewinding

A Crescent® wrench or pipe wrench.

• A tool which has a fixed jaw and a movable jaw which is controlled by a spiral gear or slide.
• It is used to install or remove bolts and nuts of various sizes.
• The wrench itself comes in a variety of lengths and jaw sizes.
• A crescent wrench has smooth jaws while a pipe wrench has serrated jaws.
• British term is adjustable spanner

1. Changing or modifying the position or alignment of two components.
2. The distance of travel that a component has.

• Groups, organizations, or individuals volunteer to clean a defined stretch periodically.

1. Abbreviation for Association of Diesel Specialists.
2. Abbreviation for Air data system

1. The act of changing the ignition timing so that the spark occurs earlier in the cycle.
   • The opposite is retard.
2. It may refer to the device which makes this adjustment.
3. The length of railway track beyond a signal which is covered by that signal

• On paper, a pattern is drawn as a curve to represent this relationship.

1. A condition in which something occurs early.
2. A product which is on the cutting edge of technology and shows the latest in new ideas and concepts.

1. Pre-paid shipping costs paid by the shipper
2. Freight costs advanced by one transportation company to another.

Located in the distributor, one of two small springs which pulls the advance weight back as the engine slows down.

One of two small weights located in a centrifugal advance assembly of a distributor.

• Sometimes supplied with a copy of the invoice and/or the bill of lading.

1. Abbreviation for Automotive Electric Association
2. Automotive Electronic Association.

1. Act of combining substance with air
2. A foaming of a liquid because air has been introduced into the fluid.
   • When it occurs in certain liquids, it decreases the efficiency of the liquid.

• More expensive but better at surviving blizzard conditions than normal separate conductors.

An extension to bicycle handlebars which project forward to give the rider an alternate riding position and a lower, more aerodynamic position.

• His elbows rest in the pads while he grabs the upright ends of the bars.
• Aerobars were popularized by triathletes and Greg LeMond.

• Aerobars popularized by triathletes and Greg LeMond, are attached to handlebars in order to provide a rider with a lower, more aerodynamic position.

• This is a factor of
  • the shape of the vehicle (drag coefficient and frontal area)
  • the objects which stick out (i.e., mirrors, mufflers, bumpers)
  • the amount of turbulence at the rear of the vehicle
  • the nature of the vehicle’s skin surface
  • the amount of air going through the vehicle for cooling and ventilation.
• The faster you go, the greater the air friction (air friction = velocity x velocity).
• The faster you go, the greater the amount of power needed to overcome this drag (power = velocity x velocity x velocity).
• Force proportional to frontal area, drag coefficient and speed squared, measured in pounds or kilograms as determined in a wind-tunnel.

• An airplane, for instance, needs positive lift to get it airborne and negative lift to help it land.
• Thus the shape of a land vehicle (car, bicycle, etc.) either promotes positive or negative lift.
• Race cars may use spoilers and wings (Air foils) to control lift.
• In vehicle design, the airflow is monitored in a wind tunnel.
• As well, aerodynamics also studies the most efficient shapes for increased speed and fuel economy.

• This improves the flow of air over the vehicle.
• A better aerodynamic stance helps the vehicle to go faster when it is going in a straight line as well as give better fuel economy.
• Also, when a vehicle sits lower to the ground, it has a low center of gravity which makes it more stable when going through turns and enables the driver to maintain a higher speed.

1. Abbreviation for across flats which is the distance on a nut (for instance) from one flat surface to the opposite flat surface, i.e., this is the size of the wrench needed to install or remove the nut.

   See

   • Across corners
2. Abbreviation for air/fuel

   See

   • air-fuel ratio
3. Abbreviation for Automatic focusing
4. Abbreviation for Audio-frequency.

1. Abbreviation for Air Flow Control
2. Abbreviation for Air flow controlled fuel injection
3. Abbreviation for Automatic frequency control

1. Abbreviation for Audio-frequency modulation.
2. Abbreviation for Air Flow Meter

A traffic marker indicating that the road is not usable.

1. A device in a diesel engine which removes the relatively warm air which enters the engine.
2. Chamber in which heat generated during compression of air is removed, allowing cool air to be piped underground.

1. The period during which the glow plugs of a diesel engine continue to operate after the engine is started.
2. The glow of a gaseous medium immediately after the cessation of electric current or downstream of an electric discharge.

1. An intermediary with legal authority to operate on behalf of the manufacturer.
2. A chemical substance with a designated purpose

1. Rock of specified quality and gradation.
2. Materials such as sand or chipped rock that are spread on paved roads to increase vehicle traction. Also called abrasives

1. The cracking, checking, or general deterioration produced by exposure of an adhesive, coating or sealer to the weather or some other given set of conditions for a length of time
2. The deterioration of rubber properties by oxidation over a period of time.
3. A change in the properties of some metals after heat treatment or cold working (i.e., hammering or bending when metal is cold).
4. The final stage of precipitation hardening, producing an increase in strength and hardness in metal alloys, due to precipitation of second phase particles from supersaturated solid solution over a period of days at room temperature, or several hours at an elevated temperature (called Artificial aging)
5. Loss of strength in the cladding or the pressure vessel in a nuclear reactor due to irradiation. Artificial aging would be the simulation of such processes by increasing the rate of irradiation to obtain information more rapidly
6. Change in the properties of a substance with time. A change in the magnetic properties of iron, e.g., increase of hysteresis loss of sheet-steel laminations; also the process whereby the subpermanent magnetism can be removed in the manufacture of permanent magnets

1. A device used to cause motion in confined fluid
2. A device for mixing paint by shaking the container.
3. A tank, usually cylindrical, which has a mixing device such as a propeller or airlift pump near the bottom. Finely ground mineral slurries (the aqueous component perhaps being a leaching solution) are exposed to appropriate chemicals for purpose of extraction of gold, uranium, or other valuable constituents. Types include pachuca tank or Brown agitator.

A tool for aiming a vehicle’s headlights.

1. Abbreviation for air conditioner.
2. A bicycling or motorcycling term describing the space or gap between the tires and the ground when the bike takes a jump. Both tires must be off the ground before it can be called ‘air’ as in the expression, ‘I really caught air on that last jump.’
3. A gas containing approximately 80% nitrogen, 20% oxygen, and a small portion of other gases and water vapor. One of the essential factors in a combustion engine (fuel, air, proper proportion of mixture, compression, timing, and spark).
4. A gas for combustion, heating, cooling, ventilation, breathing, and other uses.

1. A device which is part of the passive safety system. In the event of a collision, sensors will cause the air bag to be deployed so that your head will be pillowed by the bag instead of hitting the instrument panel or windshield.
2. A durable, inflatable bag used to force and secure freight to the inside walls of a trailer.

1. A system of braking which is usually found on large truck in which compressed air pushes against a brake piston or diaphragm in order to apply the brakes to stop or slow the vehicle.
2. An extendable device, most commonly a hinged flap on wing or fuselage, controlled by the pilot, to increase the drag of an aircraft. Originally a means of slowing bombers to enable them to dive more steeply, it is an essential flight control on clean jet aircraft and sailplanes
3. A mechanical brake operated by air-pressure acting on a piston
4. An absorption dynamometer in which the power is dissipated through the rotation of a fan or propeller.

1. A paint spray gun used for precise detailing work and custom painting.
2. The act of using an airbrush.

1. A small auxiliary combustion chamber used in certain types of compression-ignition engines, for promoting turbulence and improving combustion.
2. A space provided in the piston or cylinder to trap air during the compression stroke. It later flows out into the combustion chamber

1. A device which filters the air entering the engine to remove airborne impurities, dust, dirt, and bumblebees. Without it, impurities could cause internal wear and damage. Also called air cleaner.
2. A device using filters or electrostatic precipitators to remove indoor-air pollutants such as tobacco smoke, dust, and pollen. Most portable units are 40 watts when operated on low speed and 100 watts on high speed.

The replaceable filter which prevents impurities from the air which enters the combustion chamber. Also called air filter element.

1. A device used to control temperature, humidity, cleanliness, and movement and sometimes the air purity, in an enclosed space
2. A system of devices which causes a reduction or control of the temperature and humidity within the cab of a vehicle. It was first offered on the 1941 Packard. Two types are used in vehicles: receiver-dryer type and accumulator type.

1. Pump of a refrigerating mechanism which draws a low pressure on cooling side of refrigerant cycle and squeezes or compresses the gas into the high-pressure or condensing side of the cycle.
2. An air conditioning component which pumps, circulates, and increases the pressure of refrigerant vapor

An engine which generally has large fins or ribs and is often exposed to the outside air. The heat of the engine is dissipated through the fins of the engine. In contrast, the heat in a liquid-cooled engine is reduced by channels throughout the inside of the engine through which liquid (antifreeze) passes. Most older Volkswagens and some motorcycles use air cooled engines.

1. Mechanism designed to lower temperature of air passing through it
2. The cold accumulator used in the Lindé process of air liquefaction for the preliminary cooling of the air.

• An attachment called a spoiler which is usually located below the front bumper. Its design, shape, and placement helps to reduce the flow of air under the vehicle. It may help to increase the flow of air to the radiator and engine compartment, affect aerodynamic drag, or affect positive and negative lift.
• A barrier beneath the front bumper used to divert the flow of air beneath the car. Usually intended to reduce lift and drag.

1. An engine in which air is used as the working substance. Rapid heating from an external source expands the air in the cylinder with consequent motion being imparted to a piston. After transfer to a compression cylinder, for rapid cooling, the air is returned to the working cylinder for the next cycle. Also called hot-air engine.
2. A small reciprocating engine driven by compressed air.

1. A suction fan.
2. A vacuum pump.

The replaceable filter which prevents impurities from the air which enters the combustion chamber. Also called air cleaner element.

1. A sensor which measures the rate at which air enters the engine. In Bosch systems, any device that measures the amount of air being used by the engine. The control unit uses this information to determine the load on the engine. The two most common examples of airflow meters are the air-flow sensor used in the Bosch L-Jetronic and the air mass sensor used in the Bosch LH-Jetronic systems.
2. An instrument, mainly experimental, for measuring the airflow in ducts

1. A device in an electronically controlled fuel injection system which detects the amount of air entering the combustion chambers. Continuous injection systems use an airflow sensor plate to measure airflow volume; electronic systems use a vane or flap-type airflow sensor.
2. A detection device that provides information on the volume flow or mass flow rate of the intake air to the engine.

An aerodynamic device used to improve traction by increasing the downward force on either end of the car. It can be compared to an airplane wing with this primary difference A wing is designed to provide lift so it can fly; the air foil pushes the vehicle closer to the ground. Although they may be called ‘wings,’ they are properly air foils. They increase the cornering ability, improve Stability, but add aerodynamic drag.

1. The space between the magnetic poles or between rotating and stationary assemblies in a motor or generator
2. In a Regulator it is the distance between the contact Armature and the iron core that when magnetized, draws the armature down.
3. The distance or space between the Reluctor tooth and Pick up coil
4. The distance between the two electrodes of a spark plug.

   See

   • Spark air gap
5. Gap with points or knobs, adjusted to breakdown at a specified voltage and hence limit voltages to this value.
6. Section of air, usually short, in a magnetic circuit, esp. in a motor or generator, a relay, or a choke. The main flux passes through the gap, with leakage outside depending on dimensions and permeability.

A hammer-tool that is powered by compressed air and used for riveting, or chipping. Sometimes called an air gun or gun.

1. The upper part of a carburetor into which the air is drawn. The choke butterfly is located in this air horn.
2. It is also a term used for a warning horn which is operated by forcing compressed air through a reed.

1. Any opening introducing air into an aircraft; the opening for the main engine air is usually implied if unqualified.
2. The opening through which air enters a component such as the carburetor, fuel injection system, radiator, heating system, or ventilation system.
3. Vent in a carburetor through which air is sucked to mix with the gasoline vapor from the jet.

A paint spraying tool used in Airless spraying.

1. A pipe, hose, or duct in a vehicle which permits the flow of air or vacuum.
2. The supply line coming from an air compression tank to drive air tools or inflate tires.
3. Straight line drawn on the magnetization curve of a motor, or other electrical apparatus, expressing the magnetizing force necessary to maintain the magnetic flux across an air-gap in the magnetic circuit.

1. A bubble of air trapped in a fluid circuit which interferes with normal circulation of the fluid.
2. Device by which access is obtained to the working chamber (filled with compressed air to prevent entry of water) at the base of a hollow caisson. The worker at surface enters and is shut in an air-tight chamber filled with air at atmospheric pressure. Pressure within this air-lock is gradually raised to that used in the working chamber, so that the worker can pass out through another door and communicate with the working chamber.

1. The atmospheric pressure.
2. Tire pressure.
3. The force of air coming from a compressor used to power air tools or apply air brakes.

1. The device that supplies the fresh air needed by the Air injection system.

2. Air pump

   A reciprocating or centrifugal pump used to remove air, and sometimes the condensate, from the condenser of a steam plant.

   See

   • Air ejector
3. Any device used for transferring air from one place to another. A compressor increases the pressure, a Vacuum pump reduces the pressure and a blower causes a rapidly moving air blast
4. A device used in the emissions system to provide fresh air into a vehicle’s exhaust to help complete the combustion process and reduce emissions. To get accurate lambda measurements with the LM-1, air pumps should be temporarily disabled.

A Ratchet tool powered by air pressure from an air compressor

A forward facing aerodynamic device or opening used to Duct cool outside air to some part of the vehicle such as the carburetor Intake, the brakes, the radiator, or an Oil cooler.

1. A detection device which checks for the presence of air pollutants entering the passenger compartment. If the pollutant concentration is too high, it operates flaps to cut off the external air to the air conditioning system.
2. An air cone with a floating plate which measures air flow and determines plunger position on K-Jetronic type systems

A Suspension system using air rather than metal springs to support the vehicle and control ride motions. Air springing results in a smoother ride, because the natural frequency of vibration of an air spring does not vary with loading as it does with metal springs. Air springs can be made very soft for the lightly loaded condition and the pressure automatically increased to match any increase in load, thus maintaining a constant sprint vibration period any load.

1. Abbreviation for Air injection system.
2. Abbreviation for Automatic Idle Speed motor

1. Abbreviation for atmospheric/automatic inlet valve, a system used on early motorcycle engines in which the intake valve is held shut by a weak spring and opens by atmospheric pressure when the falling piston creates a vacuum in the cylinder.
2. Abbreviation for air injection valve

1. A display which uses a dial rather than a read-out of numbers (digital).
2. A signal that varies proportionally with the data it measures. In a computer, an analog signal is a constantly fluctuating voltage that ranges from high to low.

A speedometer which shows the speed by a needle on the dial of a gauge. It contrasts with a digital speedometer

A bicycle seat that is designed with cut out sections or bumps to accommodate your ischial tuberosities (i.e., sit-down bones).

1. A mounting point on the vehicle frame or unibody for a non-structural but stressed component, such as a seat or seat belt.
2. The stationary portion of a leading/trailing drum brake on which the heels of the brake shoes ride.
3. A heavy hook-shaped device for holding a ship at rest in water. The anchor grips the ocean bottom and is fastened to the ship by a chain.
4. An obsolete, heavy piece of equipment that has no use or function is considered euphemistically as nothing more than a boat anchor.

1. A bolt used to secure frameworks, stanchion bases, etc. to piers or foundations, and having usually a large plate washer built into the latter as anchorage
2. The bolt which goes through a bracket to secure something. British term is through bolt.

1. The stationary portion of a duo-servo drum brake on which the tops of the brake shoes rest. The secondary shoe bears against the anchor pin when the brakes are applied and the vehicle is moving forward. Conversely, when the vehicle is backing up and the brakes are applied, the primary shoe bears against it.
2. The point in a drum brake system where the braking forces are transmitted to the axle and which prevents the brake shoes from revolving with the drum.

1. The stationary portion of a leading/trailing drum brake on which the heels of the brake shoes ride.
2. A bracket, solidly attached to the vehicle suspension, on which a floating or sliding caliper mounts

1. A cylinder block that doesn’t have a deck at 90 degrees to the cylinders
2. A small wooden block used in woodwork to make joints, esp. right-angle joints, more rigid.

1. A bracket projecting from the corner of a building beneath the eaves, and not at right-angles to the face of the wall.
2. A bracket consisting of two sides set at right angles, often stiffened by a gusset. Also called gallows bracket.

A power tool (driven by electricity or compressed air) which has abrasive discs. The tool helps to remove old paint or rough metal surface

A pair of pliers with long jaws that are bent at right angles to aid in gripping something which cannot be reached with regular pliers.

1. The angle in excess of 90° by which the eccentric throw of a steam-engine valve gear is in advance of the crank.
2. The angle between the position of ignition and outer dead center in a spark-ignition engine, optimizes combustion of the fuel.

A system of parking on the side of the street where the car is about 45 degrees from parallel with the edge of the street. The British term is echelon parking

1. In an electrical circuit it is the positive pole. It is that part of an electrical circuit to which electrons are flowing.
2. The electrode at which oxidation occurs. For fuel cells that create potential, it is also the electrode towards which negative ions flow.
3. The positive terminal of an electrolytic cell
4. Zinc, aluminum, or an alloy that is attached to the hull of a vessel. As electric current moves from the vessel to the water, the anode is destroyed (oxidized). Without this anode shell, the metal hull plating would be dissolved by electrolysis.

1. Wires embedded in the glass of the windshield
2. Power operated staff which rises from the surface of the sheet metal when the radio is turned on, but is lowered almost flush when the radio is turned off. It is usually made up of several sections which telescope together. It is mounted on one of the four fenders. See Power antenna
3. A one-piece flexible rod or shorter stiff rod which is mounted to the surface of the sheet metal. It is called a ‘fixed-mast antenna’ in contrast to a power antenna. It is usually mounted in one of three basic locations: on either side of the front fender ahead of the A-pillar; either side of the rear fender behind the backlight (i.e., rear window); on the front or back of the roof. Fixed-masts are relatively trouble-free, unlike power antennas which rely upon a motor that may fail. However, some fixed-masts are subject to breakage by vandals or car-washes.

A bearing containing rollers, needles, or balls plus an inner and outer race. The bearing is designed to roll instead of slide thus minimizing friction between two moving parts. To avoid disintegration, the bearing must use lubrication (i.e., wet friction)

• It monitors the rotational speeds of the wheels and reduces hydraulic pressure to any wheel it senses locking up.
• It is controlled by both mechanical and electronic components.
• When you apply the brakes, the ABS will regulate the flow of brake fluid being delivered to the brake calipers.
• It must be remembered that a wheel cannot be steered unless it is rolling; so if the wheel is locked up, there is no steering control.
• By the use of electronic computers, the brakes rapidly alternate (at a rate of 30 times per second) from full pressure to full release.
• This process will also alternate from the left-front wheel and the right-rear wheel and switch to the right-front wheel and left-rear wheel.
• In this way both maximum braking and maximum steering control is allowed during braking.
• Before the advent of ABS, drivers were advised to pump the brakes to maintain the same effect.
• However, the human foot cannot pump the brakes faster than the computer control.
• Also, steady application of the brakes without ABS may cause brake failure (i.e., brake fade) because of the excess heat.
• Never pump the brakes if you have ABS.
• When you firmly apply the brakes with ABS, you may feel a pulsing sensation and hear a banging noise.
• The abbreviation ABS comes from the German anti blockier system.
• Sometimes called anti-skid brakes.

1. A vehicle built prior to 1915 sometimes called the brass era because of the widespread use of fancy brass fittings and brass lanterns that were a natural addition to the new ‘horseless carriage.’ The Brass era lasted from around 1905 to 1914. This was the beginning of mass produced affordable vehicles for the common public rather than the domain of the elite.
2. A vehicle built between 1880 and 1916 (inclusive)
3. A vehicle (including hardtop or convertible) built before 1950 and in original form with no modern technology, equipment, or refinements except wheels.

1. clutch antirattle spring clip

   A specially shaped wire that prevents the clutch plate and spring from making noise when no pressure is applied to the plate.

2. A device that attaches to disc brake pads to keep them from making a rattle noise when the brakes are not applied.
3. A component in disc brakes shaped like the letter X and made of spring steel. It applies radial pressure to the brake pads to prevent rattling. Also called spreader spring.

• Sometimes called the anti-sway bar, stabilizer bar, or even (incorrectly) roll-bar. It is usually a round bar which connects the left wheel suspension assembly with the right side. It may be found at the front and/or rear. Its main function is to keep both wheels rolling at the same rate when meeting bumps; but it also affects handling. A front anti-roll bar increases understeer and a rear bar increases oversteer.
• An anti-roll bar yields low roll centers with the attendant advantage of minimum jacking effect due to lateral loading and minimum lateral wheel deflection on the bump — without the disadvantage of large roll angles and consequent camber change.