Vehicle Repair Guides
Product and How To Info
Be Car Care Aware
Find a Repair Shop
An engine having two banks of four cylinders each set at an angle to form a V.
A term sometimes used to identify a block for a V-type engine, such as a V–6.2. An accurately machined metal block having a V-groove used for checking the out of roundness of a shaft or other device.
An engine having two banks or rows of cylinders set at an angle to form a V.
Used in automotive applications to drive the accessories, such as a water pump, generator, alternator, power steering, and air-conditioner compressor.
An engine having two banks or rows of cylinders set at an angle to form a V.
An enclosed space from which all air has been removed, having an absolute atmospheric pressure of near zero.
The principle-advancing ignition timing by using the vacuum generated by the engine, accomplished through the use of a mechanism attached to the distributor which moves the breaker point or pickup coil plate when it receives vacuum.
A term used for venturi vacuum amplifier.
A power-brake actuating mechanism that uses vacuum on one side of a Diaphragm as a power source to amplify braking force.
Vacuum Brake Booster
A device that uses vacuum to amplify the braking force.
A tank-like enclosure to serve the requirements of vacuum-actuated accessories.
A term used for vacuum canister or vacuum reserve tank.
Vacuum Delay Valve
An orifice-controlled valve which delays a vacuum signal to a Diaphragm, such as in the distributor vacuum-advance unit.
Vacuum Diverter Valve
A term used for vacuum pot or vacuum motor.
An analog or digital instrument used for measuring vacuum.
A rubber-like, plastic or nylon hose used to transmit vacuum.
Vacuum Hydraulic Power Unit
A unit consisting of a vacuum brake cylinder or chamber, hydraulic cylinder(s), and control valve in which driver effort is combined with force from the cylinder piston or chamber Diaphragm to displace fluid under pressure for actuation of the brake(s).
A rubber-like, plastic or nylon tube used to transmit a vacuum reading from one place to another.
A component of the air-temperature sensor that regulates the amount of vacuum signal that is applied to the servo motor.
A device having a chamber containing a vacuum Diaphragm used to create movement in a component, such as a heated air-intake blend door, when engine vacuum is routed to the chamber.
A device designed to provide mechanical control by the use of a vacuum.
A term used for vacuum motor.
Vacuum Power Unit
A device for operating the doors and valves of an air-conditioner control or duct system using vacuum as a source of power.
A device with a bleed valve that changes vacuum pressure by bleeding more or less air, thereby controlling the vacuum signal.
An electro-mechanical device used to rid a system of excess moisture and air.
Vacuum Reserve Tank
A container used to store and provide reserve engine vacuum.
The secondary bores of a four-barrel carburetor that are opened by a vacuum.
Vacuum Selector Valve
A vacuum valve that controls the vacuum motors, which, in turn, operate the airflow-control doors.
An electrical switch controlled by a vacuum.
A term used for vacuum canister, vacuum chamber, or vacuum reserve tank.
A point at which a vacuum can be released from an enclosure.
A test to determine the presence of a vacuum.
An emissions-control system component that allows vacuum advance only during certain modes of engine operation.
An electrically operated two-position valve that provides or prevents a vacuum signal to the distributor vacuum-advance unit.
A mechanical, air-operated device that closes off a vacuum line to a pot whenever the manifold vacuum pressure falls below the applied vacuum pressure.
An air-operated mechanical device that closes a vacuum line to the vacuum reserve tank whenever the manifold vacuum pressure falls below the reserve vacuum pressure.
In a power-brake system, a one-way valve on the power cylinder vacuum-supply hose connection to maintain system vacuum under certain conditions.
Vacuum-Controlled Temperature Sensing Valve
A valve that connects the manifold vacuum to the distributor advance under hot-idle conditions.
Vacuum-Suspended Power Brake
A type of power brake in which both sides of the piston are subject to a vacuum.
A list of valid bulletins supplied by the manufacturer.
A used-car price guide.
A circular-stemmed device used to control the flow of air/fuel mixture in and the flow of burned gasses out of the engine.
The angle at which the valve face is machined.
The way valves are placed in an engine, such as valves-in-head or valves-in-block.
A tire valve stem that fits through the wheel to allow the tire to be filled with air. A cap seals the valve and prevents foreign debris from entering and damaging the pin.
A term used for valve body assembly.
Valve Body Assembly
An assembly containing the parts that act as the brain of an automatic transmission, receiving messages on gear selected, vehicle speed, throttle opening and engine load, then operating automatically by sending fluid to apply the appropriate bands and/or clutches.
A term used for valve lash.
The tapered section of the valve head making contact with the valve seat.
A valve that does not close completely.
A valve that does not close at the proper time.
The bore in the cylinder head through which the valve stem passes.
A term designating the enlarged end of the valve.
The reconditioning of a cylinder head, including the valves.
A small part that fits into the retainer groove located near the tip of the valve stem to secure the valve and valve spring.
A term used for valve keeper.
The specified clearance between a valve stem end and a rocker arm on an OHV engine or valve stem end and the camshaft on an OHC engine; necessary to allow for heat expansion.
Distance that the valve moves from the closed to the open position.
A cylindrically shaped hydraulic or mechanical device in the valve train that rides on the camshaft lobe to lift the valve off its seat.
The time that the closing of the exhaust valve overlaps the opening of the intake valve at the end of the exhaust stroke and at the beginning of the intake stroke, when the intake and exhaust valves are partially open at the same time depending on the spacing of the lobe centers on the camshaft and the cam's duration.
A plate containing suction and/or discharge valves located under the compressor heads.
An area cut into the top of a piston to provide valve clearance.
Valve Position Sensor
A sensor that relays information, in electronic form, to a processor relative to the position of a valve.
A holder that keeps valves in proper order when removed, to ensure proper reassembly.
A term used for valve pocket.
A term used for valve keeper or valve key.
A device that rotates the valve while the engine is running.
The ring of hard metal to which the valve seals.
A spool-shaped valve such as that in a power-steering unit.
A small coil spring that closes the valve and keeps the lifter in contact with the camshaft.
A device mounted in the rim or inner tube to provide a method of increasing or decreasing air pressure inside a tire.
The long, slim, round part of a valve.
A term used for valve lifter.
The operational temperature of a valve that may reach 1,400°F (760°C) at the head and be as low as 100°F (37.8°C) at the stem.
The actual opening and closing of the valves in relationship to the number of degrees of crankshaft rotation.
An overhead-valve engine with the valves in the head.
The end of a valve lifter that rides on the camshaft.
A replacement valve seat.
The tendency for some valves to contact the seat in such a manner as to wear away the seat.
A device on the valve stem that holds the spring in place.
Valve-Spring Retainer Lock
A device on the valve stem that locks the valve-spring retainer in place.
The area in the cylinder where the fixed end of the valve spring is attached.
That part of the valve stem used to position the keepers and locate the valve retainer.
The boss in the cylinder head that supports and holds the rocker-arm stud.
An assembly containing the expansion valve, suction throttling valve, desiccant, and receiver.
The many parts making up the valve assembly and its operating mechanism.
A box-shaped, light truck with a forward cab.
A van that has been customized as a camping vehicle or for some other specific use.
A flat, extended surface such as that on an impeller of a pump.
A pump having small vanes in an elliptically shaped housing.
The scientifically designed and positioned fins that direct or redirect fluid flow inside the torque converter.
A gaseous form of matter.
Lines used to carry gas or vapor.
A condition in carbureted engines where excessive heat has caused the fuel in the fuel line or fuel pump to boil, blocking the flow of fuel to the carburetor and preventing the engine from starting.
Vapor Recovery System
That part of the evaporative-emissions control system that prevents gasoline vapors from escaping to the atmosphere by trapping them in the charcoal canister to be drawn into the engine and burned when the engine is started.
The provisions of a fuel nozzle that prevent gasoline vapors from entering the atmosphere when a vehicle is being fueled.
Vapor return Line
A hose used to carry fuel vapor from the fuel pump or the liquid vapor separator back to the fuel tank.
Vapor Saver System
A term used for vapor recovery system.
A term used for vapor/liquid separator.
Part of the evaporative-emissions control system that prevents liquid (gasoline) from flowing through the vent line to the charcoal canister.
The process of turning a liquid, such as gasoline, into a vapor which is often accomplished after the atomized fuel leaves the carburetor.
A resistor that provides for an infinite number of resistance values within a specific range, such as a rheostat or potentiometer.
Variable Venturi Carburetor
A carburetor having an arperture that increases or decreases in size as controlled by intake manifold vacuum.
A term used for variable venturi carburetor.
An engine designed so that displacement can be altered by activating and deactivating cylinders.
A valve spring with unevenly spaced coils.
A torque-converter design for transmissions used in off-highway, special-equipment applications.
Variable-Rate Coil Spring
A spring having an average spring rate based on load at a predetermined deflection in a variety of wire sizes and shapes.
A spring that increasingly resists deflection as the load is increased, such as a coil spring having its coils closer together at one end, or a single-leaf spring that is thinner near the ends.
Variable-Ratio Power Steering
A power-steering system in which the response of the vehicle wheels varies according to how much the steering wheel is turned.
A power-steering system that varies the steering ratio at different vehicle speeds.
A fan having a fluid-filled or thermostatic-actuated clutch that senses the temperature of the air coming through the radiator and adjusts its speed accordingly.
Baked on oil and grease.
An abbreviation for volumetric efficiency.
A means of conveyance or transport, sometimes motorized, that moves on wheels, runners, or tracks.
A generic term for a car or truck.
The combination of binder and solvents or diluents, which are used to put the binder in a liquid, usable form.
Vehicle Body Clearance
The distance from the inside of the inner tire to the spring or other nearest frame or body structure.
Any of several standard methods of classifying vehicles such as engine type, body/frame construction, fuel consumption structure, or type of drive. The classifications most common to consumers are the use of body shape, seat arrangement, and number of doors.
Vehicle Construction Types
Passenger cars of today use one of two types of construction conventional body-over-frame and unitized or unibody.
Vehicle Emission-Control Information
The emission-control information shown directly on a label on each vehicle.
Vehicle Engine Tests
A test involving engine rigs or vehicles being placed into cold rooms at −22°F to −40°F (−30°C to −40°C) that are started after a cold-soak period to test all engine components in a cold-start situation.
Vehicle Identification Number (VIN)
The vehicle's identification number, located on the left front of the dashboard, which represents various data such as the model of the vehicle, year, body, style, engine type, and serial number.
Vehicle Off Road (VOR)
A vehicle that is out of service for lack of parts to repair it.
Vehicle On-board Radar (VORAD)
A vehicle warning system that provides drivers additional reaction time to respond to a potential danger.
An optional type of brake system used to supplement or assist the regular service brakes on a heavy duty truck.
A term used for traction.
Vehicle Vapor Recovery (VVR)
A term used for vapor recovery system.
The rate of motion in a particular direction.
The short tubes attached to carburetors that are tuned to a resonate frequency that forces more air into the carburetors. Also referred to as stacks.
A brand of sintered-metal brake linings.
A controlled opening through which air or other vapors can escape.
Ventilate the Block
To throw a rod through the block.
A disc-brake rotor whose friction surfaces are separated by cooling fins having open, ventilated passages between each face for heat dissipation.
To circulate fresh air through a space or system.
A narrow area in a pipe through which a liquid or a gas is permitted to flow.
The constriction of the air passageway between the choke and throttle plates in a carburetor, so as air flows past this constriction, its velocity increases and a partial vacuum is produced, thereby promoting a flow of gas from the main gas nozzle.
The condition of a gas or liquid flowing through a pipe and the pipe diameter is narrow in one place, the flow speeds up in the narrow area, causing a lower pressure in the narrow area, which may be defined as a venturi.
Venturi Vacuum Amplifier
An exhaust-gas recirculation system having a device that uses the weak venturi vacuum signal to regulate the application of strong manifold vacuum to the EGR valve, usually including a reservoir that supplies sufficient vacuum when the engine is producing too little for proper operation.
The weight on a tire that serves as the input for a tire's performance.
The position of welding in which the weld axis is approximately vertical.
The maximum recommended vertical downward force that can be safely applied to a coupling device.
A rapid back and forth motion.
A device designed to dampen or reduce crankshaft torsional (twisting) vibrations that might otherwise cause crankshaft cracks or breakage.
An induction coil constructed so that the magnetism of the core operates the make and break or vibrator of the primary circuit.
Short for Victoria.
A four-wheel carriage with a two-seat passenger compartment and a separate, high seat in the front for the driver, first used to transport England's Queen Victoria.
A close-coupled, two-door sedan first offered by Ford in the early 1930s.
The area at a race track where the winner of an event is honored.
An abbreviation for vehicle identification number.
A historic car; one built before 1925.
Friction between moving parts, such as in a compressor, resulting from using an oil that is too heavy or thick.
The resistance of a fluid to flowing.
The numerical rating of a fluid's resistance to flow.
A number to indicate the change in viscosity of an oil when heated.
A numerical indicator of the viscosity of an engine oil established by the American Petroleum Institute.
Tendency to resist flowing.
A coupling device having input and output shafts fitted with thin, alternating discs in a closed chamber filled with fluid.
A type of crankshaft harmonic balancer that contains a liquid to control engine vibration.
A cooling fan attached to a viscous coupling.
The friction between layers of a liquid.
Viscous-Drive Fan Clutch
A belt-driven, water-pump mounted, liquid-filled or thermostatically controlled cooling fan clutch that drives the fan fast at high temperatures and slow at low temperatures.
An abbreviation for volatile organic compound.
A computer-controlled phoneme generator capable of reproducing the phonemes used for basic speech, putting them into the right combination to create words and sentences.
Voice Warning System
A warning system that uses a voice synthesizer to alert the driver of monitored conditions.
A French term for carriage for all, loosely translated to bus.
Memory that does not retain data when power is interrupted to the computer.
Volatile Organic Compound (VOC)
A term that relates to chemicals that are negligibly photochemically reactive.
The measure of how rapidly a liquid evaporates.
A Volkswagen hot rod.
A unit of measure of electrical force required to produce a current of one ampere through a resistance of one ohm.
A specific quantity of electrical force.
A reduction of voltage in an electrical circuit.
The electrical pressure at a particular point.
An electrical device to control the output of a generator or alternator.
A device having a junction of dissimilar metals that provide a small voltage output.
An instrument used to read the pressure behind the flow of electrons.
Volumetric Efficiency (VE)
A percentage ratio that varies with the engine's rpm measuring the difference between the air-fuel mixture actually entering a cylinder and the amount that can enter under ideal conditions.
An abbreviation for vehicle off road.
An abbreviation for vehicle on-board radar.
Vortex Oil Flow
The circular oil-flow path as it leaves the impeller, travels to the turbine, then through the stator and back into the impeller.
A mass of whirling fluid within a torque converter when impeller speed is high and turbine speed is low.
A process of treating raw rubber with heat and pressure.
An abbreviation for vehicle vapor recovery.
Glossary Navigation for V
V - Vacuum Modulator
Vacuum Motor - Value Guides
Valve - Valve Position Sensor
Valve Rack - Valve-Stud Boss
Valves-in-Receiver - Variable-Displacement Engine
Variable-Pitch Spring - Vehicle Retarder
Vehicle Traction - Victoria
Victory Lane - Volatile Memory