| I
| Intensity, or Iodine An element with the atomic number of 53 |
| I-4
| An acronym for an inline four-cylinder engine. |
| I-6
| A term used to identify a six-cylinder in-line engine |
| I-beam axle
| A beam axle having an I-shaped cross section. |
| I-beam rod
| A connecting rod having an I-shaped cross section. |
| I-head
| An overhead valve engine having both intake and exhaust valves directly over the piston. |
| I-head engine
| An overhead valve engine with the valves in the head.. |
| i.d.
| An acronym for internal diameter or inside diameter. |
| I/M
| An acronym for inspection maintenance usually referring to state emissions inspection and testing programs |
| I/M 240
| A 240-second emissions-inspection program that used loaded-mode testing that simulates the federal urban test cycle for certifying new vehicle-emissions performance. |
| I/O
| Input/Output |
| I4
| A term used to identify a four-cylinder in-line engine |
| IAC
| Idle air control or inlet air control |
| IAC-BPA
| Idle air control bypass air |
| IACV
| Idle air control valve |
| IAM
| Idle air management |
| IAT
| An acronym for intake air temperature sensor. |
| iATN
| The largest network of automotive technicians in the world This group of over 45,000 professional automotive technicians from 129 countries gather to exchange technical knowledge and information from around the globe. with an experience base of more than 924,690 years of experience (see www.iatn.net for additional information) |
| IAVC
| Idle air valve control |
| IBOB
| An acronym for Intelligent Break Out Box. A box placed in series between the powertrain control module and the wiring harness to provide a place to probe the circuit and identify problems. The Intelligent brake-out-box also interfaces with the scantool for circuit information and analysis |
| IBP
| Integral back-pressure |
| IC
| 1. An acronym used for internal-combustion engine. 2. A complete electronic circuit of many transistors and other devices, all formed on a single silicon semiconductor chip. |
| ICE
| An acronym for internal-combustion engine. |
| ice-melting capacity
| A refrigeration effect equal to the latent heat of fusion of a stated weight of ice, at 144 Btu per pound. |
| ICM
| Ignition control module |
| icon
| A small picture that represents an object or program and acts like a button to operate whatever program it represents. |
| ICVS
| Idle control vacuum solenoid |
| ideal air/fuel ration
| A term used for Stoichiometric air/fuel ratio. |
| Ideal Fuel Mixture
| The air/fuel ratio which provides the best performance, while maintaining maximum conversion of exhaust emissions, typically 14.7:1 |
| ideal humidity
| Most people are comfortable at a relative humidity of 45% to 50%. |
| ideal temperature
| Most people are comfortable at a temperature from 68? to 72? F (20? to 22.2?C). |
| IDI
| [1] An acronym for indirect injection. [2] Intergrated Direct Ignition |
| idiot box
| An automatic transmission. |
| idiot light
| The system-malfunction warning lights on a dashboard. |
| idiot proof
| A product that is designed to be as simple as possible to operate. |
| idle
| The engine speed with no load and the accelerator pedal fully released. |
| idle air bleed valve
| A device used to control the amount of airflow into the idle fuel mixture prior entering the carburetor idle system (M/C) solenoid on |
| idle air-control valve
| A General Motors electrically operated valve that, on commands from the engine-control computer, varies the size of an air passage that bypasses the throttle plate of an electronic fuel-injection system, thus controlling idle speed. |
| idle circuit
| The system within a carburetor that meters fuel when the engine is running at low rpm. |
| idle compensator
| A term used for engine-idle compensator or hot-idle compensator. |
| idle limiter
| A device that controls the maximum richness of the idle air/fuel mixture in the carburetor. |
| idle load compensator
| (ILC) This device is used to control throttle angle during long deceleration such as coasting down a long grade and extends the WOT position to prevent engine stalls. |
| idle mixture
| The air/fuel mixture supplied to the engine while idling. |
| idle port
| An opening into the carburetor throttle body through which the idle system discharges fuel. |
| idle relearn
| The routine of the computer that resets idle requirements when a disconnected battery has been reconnected. |
| idle speed
| The speed at which an engine idles in revolutions per minute (rpm), usually between 600 and 850 rpm. The idle speed is specified on the under-hood emissions decal. |
| Idle Speed Control Motor
| Regulates the throttle valve position and is controlled by the computer |
| idle system
| The passages of a carburetor though which fuel is fed when the engine is idling. |
| idle vent
| An opening in an enclosed chamber through which air can pass under idle conditions. |
| idle-limiter cap
| A plastic device pressed over a carburetor's idle-mixture screw that limits the amount of adjustment during service to help eliminate excessive air pollution that is caused if the mixture is too rich. |
| idle-mixture adjustment
| An adjustment made on carbureted engines by removing the antitampering plugs and turning the idle-mixture screws until the proper idle mixture is achieved. Setting the idle mixture on an emissions-controlled engine may require monitoring exhaust CO or using a special procedure called propane enrichment. |
| idle-mixture screw
| A screw on the carburetor used to adjust engine-idle speed. |
| idle-speed adjustment
| The idle speed on carbureted engines without computer idle-speed control is set by turning a screw that opens or closes the throttle plates. On fuel-injected engines without computer idle-speed control, idle speed is set by turning an idle-air bypass screw that allows air to bypass the throttle plates. Idle speed is not adjustable on engines with computer idle-speed control. |
| idle-stop solenoid
| An electromagnetic device mounted on the carburetor linkage that maintains the proper throttle opening for specified idle speed while the ignition is on, but allows the throttle to close further when the ignition is switched off, reducing the amount of air that can enter the engine and the likelihood of dieseling. |
| idler arm
| A pivoting component that supports the right side of the steering relay rod in much the same manner as the pitman arm supports the left side. |
| idler eccentric
| A device used in a belt-drive system using the idler pulley as a means of tightening the belt. |
| idler gear
| 1. A gear connecting two other gears in a manner so that they will turn in the same direction. 2. A gear that transmits movement between the drive and the driven gears, but does not affect the speed relationship of those gears. |
| idler pulley
| A pulley that is used to adjust the belt in a belt-driven system. |
| IDM
| Ignition diagnostic monitor |
| IEC
| International Electrotechnical Commission |
| IES
| Idle enrichment system |
| IESR
| Ignition electronic spark retard |
| if you can't find 'em, grind 'em
| An admonition to a driver who misses a shift. |
| IFI
| an acronym for Inline Fuel Injection |
| IFS
| Inertia fuel shut-off |
| ignition
| The firing of a spark plug to ignite the air/fuel mixture in the combustion. |
| ignition advance
| The moving forward, in time, of the ignition spark relative to the piston position. |
| ignition coil
| A transformer containing a primary and secondary winding that acts to boost the battery voltage of 12 volts to as much as 30,000 volts to fire the spark plugs. |
| ignition distributor
| A term used for distributor. |
| ignition map
| A chart showing the precise advance and retard of the ignition on an electronic control-equipped engine. |
| ignition points
| A term used for points. |
| Ignition Reference Signal
| Signal used by the ECM to determine engine RPM and crankshaft position. |
| ignition reserve
| The difference between the minimum available and maximum required voltage for proper operation. |
| ignition resistor
| A resistance element in series with the primary circuit to reduce the voltage supplied to the coil during engine operation. |
| ignition retard
| The moving back in time of the ignition spark relative to the position of the piston. |
| ignition switch
| A five-position switch that is the power distribution point for most of the vehicle's primary electrical systems. The spring loaded START position provides momentary contact and automatically moves to the RUN position when the key is released. The other switch detent positions are ACCESSORIES, LOCK, and OFF. |
| ignition system
| The major components, such as the battery, coil, ignition switch, distributor, high-tension wiring, and spark plugs, that provide the right spark at the right time to ignite the air/fuel mixture. |
| ignition temperature
| The lowest temperature at which a combustible material will ignite and continue to burn independent of the heat source. |
| ignition timing
| The timing of the spark, expressed in crankshaft degrees, in relation to top dead center. |
| ignition timing-retard sensor
| A term used for knock sensor. |
| IHC
| International Harvester Corporation |
| IHP
| An acronym for indicated horsepower. |
| IHRA
| An acronym for the International Hot Rod Association. |
| IKF
| An acronym for the International Karting Federation. |
| ILC
| Idle load compensator or idle load control |
| IM
| Ignition module |
| IM240
| Inspection and maintenance test |
| IMACA
| An acronym for International Mobile Air Conditioning Association. |
| IMCA
| An acronym for International Motor Contest Association. |
| IMEP
| An acronym for indicated mean effective pressure. |
| impact failure
| The failure of a part or assembly due to repeated impact or off-square seating. |
| impact hardness
| The hardening of a part caused by repeated impacts. |
| impact particle cleaning
| A method of cleaning parts using air-propelled glass beads. |
| impedance
| The total opposition a circuit offers to the flow of current. Including resistance and reactance and is measured in Ohms. Most digital meters have 10,000,000 Ohms of impedance to protect computer circuits |
| impeller
| 1. A rotor or rotor blade used to force a gas or liquid in a certain direction under pressure. 2. A rotor that transmits motion such as a centrifugal pump, supercharger, turbine, or fluid coupling. |
| impulse
| A momentary surge in voltage or current. |
| impurities
| 1. Any unwanted element or compound in a metal or semiconductor 2. An intentional doping element in a semiconductor. |
| IMRC
| [1] Integrated module relay controller [2] intake manifold runner control |
| IMS
| An acronym for the Indianapolis Motor Speedway. |
| IMSA
| An acronym for the International Motor Sports Association. |
| In
| Indium An element with the atomic number of 49 |
| in and out box
| A racing transmission having a neutral and single direct drive forward gear. |
| in the chute
| Staged for a drag race. |
| in-car sensor
| A term used for in-car temperature sensor. |
| in-car temperature sensor
| A thermistor used in automatic temperature-control systems for sensing the in-car temperature. |
| in-duct sensor
| A thermistor used in automatic temperature control units for sensing the in-duct returns air temperature. |
| in-H2O
| An acronym for inches of water column. |
| in-Hg
| An acronym for inches of mercury. |
| in-lb
| An English measure of torque. |
| in-line engine
| An engine having all its cylinders in one line or row. |
| in-line steering gear
| A type of integral system. |
| in-phase
| The in-line relationship between the forward coupling-shaft yoke and the drive-shaft slip yoke of a two-piece drive line. |
| in-vehicle sensor
| A term used for in-car sensor. |
| in-vehicle temperature sensor
| A term used for in-car sensor or in-car temperature sensor. |
| inactive spring coil
| Inactive coils located at the end of a spring introduce force into the spring when a wheel strikes a road irregularity. |
| inadequate crush
| An insufficient crush on a pair of bearing shells allowing excessive clearance between the bearings and the shaft. |
| inadequate joint penetration
| Joint weld penetration that is sufficient to properly bond the base metals. |
| inboard
| Toward the centerline of the vehicle. |
| incandescence
| Glowing due to heat. |
| incandescent
| That which gives light or glows at a white heat. |
| incandescent lamp
| An electric lamp or bulb containing a thin wire or filament of infusible conducting material. |
| inch pound
| the amount of work required to rase one pound one inch |
| inch-pound
| An English measure of torque. |
| inches of mercury (in-Hg)
| A term used to designate a vacuum on the English scale. |
| inches of water column (in-H2O)
| An engineering term used to designate pressure such as inches of mercury or kilo Pascals. |
| inclined surface
| 1. A slope or slanted surface 2. A valve rotator. |
| included angle
| 1. Sum of the kingpin or ball-joint inclination angle and the camber angle of a vehicle's front wheel. 2. The sum of the camber angle added to the steering axis-inclination angle. 3. The angle included between the outer surfaces of the link-plate contours of a silent chain that meshes with the sprocket tooth form. |
| incomplete joint penetration
| Joint penetration that is unintentionally less than the thickness of the weld joint. |
| incompressible
| A volume of liquid that remains the same under pressure |
| independent front suspension (IFS)
| A suspension-system method of supporting the chassis on the wheels without the use of rigid axles where the movements of the two front wheels are not interdependent; one wheel does not force the other wheel to change its plane of rotation. |
| independent publishers
| Publishers that provide service and repair information on a variety of subjects, such as automobiles. |
| independent rear suspension (IRS)
| 1. A suspension system in which both rear wheels are free to move independently of the other, providing a reduction of unsprung weight as well as overall vehicle-weight reduction. 2. An independent suspension system at the rear of a vehicle. |
| independent service
| General or specialty service provided by independent garages on all types and makes of vehicles. |
| independent suspension
| A suspension system by which a wheel on one side of a vehicle can move vertically without affecting the wheel on the other side, and wheel jounce or rebound travel of one wheel does not directly affect the movement of the opposite wheel. |
| index
| 1. To examine and adjust rod journal spacing and alignment. 2. The elapsed time assigned to various classes in drag racing used to calculate starting-time differences for handicap or bracket racing. 3. Installing a camshaft relative to the crankshaft so the valves open and close at precisely the right time. |
| Indianapolis Motor Speedway (IMS)
| A very popular race course, not in Indianapolis, but in Speedway, Indiana. |
| Indianapolis Raceway Park (IRP)
| Better known as Indy. The site of the U.S. Nationals on Labor Day weekend. |
| indicated horsepower (IHP)
| A measurement of power developed by the combustion processes in the cylinders, not considering friction. |
| indicated mean effective pressure (IMEP)
| The average of the pressures developed in the cylinders during the four-stroke cycle, intake, combustion, exhaust, and compression. |
| indicated speed
| The vehicle as indicated on a speedometer. |
| indicated torque
| Torque as calculated from the indicated mean effective pressure, which is an actual indication of output developed within the cylinders. |
| indirect injection (IDI)
| A system in which fuel is injected into a prechamber, where it is ignited before entering the main combustion chamber. |
| Indium
| One of the chemical elements. Atomic number 49. Symbol In. With three electrons in its valance shell it is used as a doping agent to create a "P" type semiconductor. |
| Inductance (L)
| The capability of a coil to store energy in a magnetic field surrounding it which results in a property that tends to oppose any change in the existing current flow in the coil. |
| induction
| 1. A synonym or intake. 2. A process whereby an electromagnet or electrically charged object transmits magnetism or an electric current to a nearby object without making physical contact. 3. The process by which a voltage is induced into a conductor by a changing magnetic field. |
| induction coil
| An electrical device that receives low battery voltage in its primary winding and delivers pulsating high voltage in its secondary winding as the primary field is energized and collapsed by use of a set of points. |
| induction hardening
| A process of hardening the surface of a part by placing electric coils next to it. |
| inductive reactance
| An opposing current or voltage created in a conductor whenever there is a charging current flow in that conductor. |
| Inductive Reluctance
| A statement of a material's ability to strengthen the magnetic field around it |
| Indy
| 1. Short for Indianapolis Motor Speedway. 2. Short for Indianapolis Raceway Park. |
| Indy 500
| A race held every Labor Day weekend at Indianapolis Motor Speedway. It is an American classic, the single largest spectator-attended sporting event in the world. |
| Indy car
| An open-wheeled vehicle built especially for Indy and CART racing. |
| Indy Lights
| A junior series of Indy racing sponsored by CART. |
| inert gas
| A gas that normally does not combine chemically with materials. |
| inertia
| 1. The property of a moving object that causes it to resist any change in speed or direction. 2. The tendency of an object in motion to keep moving and the tendency of an object at rest to remain at rest. |
| inertia lock retractor
| A passive seat-belt system that used a pendulum mechanism to lock the belt tightly during a sudden change in movement. |
| inertia weight
| A small, steel flywheel used to dampen drive-line vibrations on certain applications; generally located on the slip yoke, drive pinion yoke, or near an end of the drive shaft. |
| inertial scavenging
| An exhaust system that uses the momentum of flowing gases to pull more gasses through. |
| infield
| an area enclosed by an oval track or a road course. |
| infinite
| Having no limits whatsoever. Boundless, thus, an infinite number is one more than the largest possible number. |
| inflation pressure
| The amount of air pressure required to inflate a tire, measured in psi or kPa. |
| information center
| The electronic display in some luxury vehicles that shows such data as the date, inside and outside temperature, trip distance traveled and distance remaining, time of departure and estimated time of arrival, average and current speed, average and instantaneous fuel economy, fuel used and remaining, and often, an appointment reminder. |
| information sheet
| A form that is used to record pertinent information about a vehicle. |
| information superhighway
| A popular buzzword to describe the internet. |
| infrared exhaust analyzer
| An instrument able to detect and measure hydrocarbons, carbon monoxide, carbon dioxide, and oxygen levels. |
| inhibitor
| A substance used to reduce the rate of a chemical or electrochemical reaction. |
| injected
| An engine equipped with a fuel injector. |
| injection cylinder
| A term used for oil-injection cylinder. |
| injection valve
| A term used for fuel injector. |
| injector
| 1. The tube or nozzle through which fuel is injected into the intake airstream of the combustion chamber. 2. A term used for fuel injector. |
| injector body
| The housing for a fuel-injection system. |
| injector fuel
| The fuel that is stored inside the injector prior to use. |
| injector tube
| The copper or brass tube used in diesel cylinder heads to col fuel injectors and seal combustion pressures. |
| inlet
| A synonym for intake. |
| innards
| The internal parts of an assembly. |
| inner liner
| A synthetic, gum-rubber layer molded to the inner surface of a tire for sealing purposes. |
| inner shaft
| A shaft upon which the inner end of the upper control arm pivots in a front suspension system. |
| inner tube
| An inflatable rubber bladder mounted inside some tires to contain the air. |
| inner-cam clutch
| A one-way roller clutch that has the cam profile surfaces on the inner element. |
| Input
| An electrical signal that the PCM uses to calculate current engine condition |
| input member
| The drive member of a planetary gearset. |
| input retarder
| A paddle-wheel-type unit located between the torque converter housing and the main housing in the retarder housing; primarily for over-the-road operations. |
| input shaft
| The transmission shaft that receives power from the engine. |
| input-voltage
| The voltage level from any sensors to the computer that represents the current sensor condition |
| insert valve guides
| Replaceable valve guides. |
| insert valve seats
| Replaceable valve seats. |
| inside diameter (i.d.)
| The diameter of the inner walls of a pipe or tube. |
| inside-vehicle lubrication services
| Work performed inside the vehicle during a chassis lubrication such as changing the mileage sticker, lubricating the ignition-lock cylinder and the glove-compartment hinges and lock, and inspecting safety-related items. |
| inspect
| To examine a component or system for any audible or visual signs of a defect. |
| inspection
| The process of measuring, examining, testing, gauging, or otherwise comparing the unit with the applicable requirements or specifications. |
| inspection maintenance (I/M)
| The periodic and systematic inspection and maintenance of a vehicle's ignition, fuel, and emissions-control systems, commonly used to refer to state / county emissions inspection and testing programs |
| install
| To set up an accessory part or kit for use in a vehicle. |
| installed height
| The distance from the valve-spring end to the valve-spring seat. |
| instant center
| An imaginary center point around which a wheel appears to pivot. |
| insulated return system
| The ground wire of a two-wire electrical system. |
| insulation
| Any material that blocks the flow of electricity. Any material containing more than 4 electrons in its valance shell. |
| insulation tape
| Tape (usually cork) used to wrap refrigeration hoses and lines to prevent condensate drip. |
| insulator
| 1.A material with high electrical resistance that supports or separates conductors to prevent undesired flow of current to other objects. 2. A material that contains less than four electrons in its valance shell. |
| insulator ribs
| In a spark plug, unevenly spaced circular ridges on the upper section of the insulator to reduce or prevent flashover of the high voltage from the terminal to the lower shell. |
| Insurance Information Institute
| A public information and communications association. |
| Insurance Institute for Highway Safety
| A highway and vehicle safety research organization. |
| intake
| The point at which a fluid or gas enters a pipe or channel. The act of taking in. |
| intake air temperature sensor
| (IAT) A thermistor device that senses intake air temperature by changing it's resistance as a negative temperature coefficient resister. |
| intake manifold
| A metal component used to duct 1. The air/fuel mixture from the carburetor to the intake parts. 2. Air in an injected engine to the intake ports. |
| intake over exhaust (IOE)
| An engine design having intake valves in the cylinder head and exhaust valves in the block |
| intake ports
| 1. Passages in the cylinder head that direct air/fuel mixture from the intake manifold to the intake valves. 2. Passages in an L-head engine block that direct the air/fuel mixture from the intake manifold to the intake valves. 3. Passages in the head or block of an injected engine that direct air to the intake valves from the intake manifold. |
| intake stroke
| A downward stroke of a piston that draws the air/fuel mixture into the cylinder. |
| intake valve
| A valve that opens to admit the air/fuel mixture. |
| integral
| Internal or built-in as a part of the whole. |
| integral valve guide
| A valve guide machined into the cylinder head. |
| integral valve seat
| A valve seat machined into the cylinder head. |
| integral-type power steering
| A steering system with a built-in power assist. |
| integrated ABS
| An antilock brake system in which the ABS hydraulic components, the standard brake hydraulic components, and a hydraulic power booster are joined in a single, integrated hydraulic system. |
| integrated circuit
| A complete electronic circuit of many transistors and other devices, all formed on a single silicon semiconductor chip. |
| Integrated Direct Ignition
| The type of ignition system used on GM engines that produces the ignition spark without the aid of a distributor |
| Intel
| The worlds largest manufacturer of computer chips. |
| Intensity Grading
| Frequency-of-occurrence information that is essential to understanding what the waveform is realy doing |
| Inter Industry Conference on Auto Collision Repair
| An international, collision-repair training organization. |
| inter-axle differential
| A third differential between the front and rear differentials that permits differences in speed between the front and rear driving axles. |
| inter-changeability
| The basis of mass production; the production of parts that are consistent in size, tolerance, and specifications. |
| intercooler
| A radiator-like heat exchanger between the supercharger or turbocharger and the engine to cool the air/fuel mixture. |
| interface
| 1. Something that connects two separate entities; a user interface is the part of a program that connects the computer with a human operator (user). 2. An interface can also connect a computer to another computer or a computer to peripheral devices |
| interface fit
| A term used for interference fit. |
| interference angle
| The difference between the valve face angle and the valve seat angle. |
| interference valve angle
| The difference between the valve face angle and the valve seat angle, usually one or two degrees. |
| Intergrated Circuit
| A complex circuit of thousands of transistors, diodes, resistirs, and capacitors that are formed into a small silicon chip |
| Intergrator
| A GM term for Short term fuel trim |
| interior lights
| The inside vehicle-lighting system, including courtesy, dome, map and instrument- panel lights. |
| interlock
| An electrical-circuit arrangement that prevents a second operation from taking place until the first operation is completed. |
| intermediate gear
| A small torque increase obtained from a planetary gear set when the sun gear is held and power is applied to the internal gear. |
| intermediate lever
| part of the parking brake linkage under the vehicle that increases application force and work with the equalizer to apply it equally to each wheel. |
| intermittent
| A fault that occurs now and then in an electrical circuit, referring to occasional opens, shorts, or grounds |
| intermittent duty
| A service requirement that demands electrical or mechanical operation for alternate intervals of load and no load; load and rest; or load, no load, and rest. |
| intermittent problem
| A fault that occurs now and then in an electrical circuit, referring to occasional opens, shorts, or grounds |
| internal gear
| A gear with teeth pointing inward toward the center of the orifice. |
| internal-combustion engine (IC)
| An engine that burns the air/fuel mixture in a chamber inside the engine cylinder, like a conventional reciprocating engine or a rotary engine. |
| International Carwash Association/National Carwash Association
| A trade association consisting of carwash owners, operators, manufacturers, distributors, and suppliers. |
| International Franchise Association
| A trade association representing franchisors, franchisees, suppliers, educational institutions, and franchise associations from other countries. |
| International Hot Rod Association (IHRA)
| A drag-racing sanctioning body. |
| International Karting Federation (IKF)
| A major kart-race sanctioning body. |
| International Motor Contest Association (IMCA)
| An automobile race-sanctioning body of drivers, owners, and mechanics created to establish rules, regulations, and specifications. |
| International Motor Sports Association (IMSA)
| A road-racing sanctioning body. |
| International Race of Champions (IROC)
| An annual series for top drivers from various forms of oval-track and road racing who are invited to compete, driving identical spec cars. |
| International Show Car Association (ISCA)
| A promoter of International Championship Custom Car Shows. |
| International Truck Parts Association (ITPA)
| A trade association of companies that buy and sell used and remanufactured heavy-duty truck parts. |
| internet
| A global network connecting billions of computers accessible at no charge. |
| internet explorer
| A Microsoft web browser; enables you to view web pages. |
| Interpolation
| A "Connect the dots" processing technique to estimate what a fast waveform looks like based on only a fue sampled points |
| interpole
| A small field pole placed between the main field poles and electrically connected in series with the armature of an electric rotating machine. |
| Interrupter
| A device used to block a signal |
| intrinsically safe
| A system that is incapable of releasing sufficient electrical or thermal energy under any condition to cause ignition of a specific hazardous mixture in the atmosphere, even in its most ignitable concentration. |
| intrusive diagnostic test
| Any on-board test run by the PCM which could have an effect on vehicle performance or emissions. |
| Intrusive Test
| This is any on-board test run by the diagnostic management system which will have an effect on the vehicles performance or emission levels |
| inversion valve
| A normally open air valve used primarily in parking and emergency brake systems. |
| inverted start
| When cars are started in the reverse order of their qualifying times, in oval-track racing. |
| Inverter
| 1. A device used to convert the direct current produced by a fuel cell to alternating current for use at the moter. |
| investigation table
| A term used for component location table. |
| IOD
| Ignition off drain a Chrysler term for parasitic load |
| IOE
| An acronym for intake over exhaust. |
| ion
| 1.An atom or group of atoms having an electrical charge, either positive or negative, resulting from orbiting electrons being removed or added. 2. Any atom with more or less electrons than protons. |
| ionic bond
| A primary bond arising from the electrostatic attraction between two oppositely charged ions, such as electrostatic painting. |
| ionosphere
| Anything in the upper atmosphere above the earth by about 25 miles 130,000 ft. |
| IP
| Instrument panel |
| IPC
| Instrument panel cluster |
| IPS
| Idle position switch |
| IPTO
| Independent power take off |
| Ir
| Iridium An element with the atomic number of 77 |
| IRCL
| An acronym for Infrared Remote Central Locking System |
| IRCM
| Integrated relay control module |
| IROC
| An acronym for International Race of Champions. |
| iron
| A basic element with the chemical symbol Fe. |
| iron-core coil
| A coil or transformer which uses an iron core to enhance the magnetic coupling between windings, increasing the magnets flux-density. |
| irontite
| A tradename for the process of filling cracks in cast-iron cylinder heads and blocks using tapered plugs. |
| IRP
| An acronym for Indianapolis Raceway Park. |
| irs
| [1] An acronym for Internal Revenue Service [2] An acronym for International Show Car Association |
| ISA
| Idle speed actuator |
| ISC
| An acronym for Idle speed Control |
| ISC-BPA
| Idle speed control-bypass air |
| ISCA
| An acronym for International Car Show Association. |
| Isky
| The trade name of a popular brand of camshaft and valve-train components.. |
| islands of steel
| A term used for hard spots. |
| ISO
| an acronym for the International Standards Organization |
| ISO 9141
| International Standards Organization recommended data communication network interface. |
| ISO Diagnostic Protocol
| International Standards Organization Diagnostic Protocol used by most European, Asin and some Chrysler vehicles and used the KWO protocol |
| ISO flare
| A type of tubing flare connection in which a bobble-shaped end is formed on the tubing; also called a bubble flare. |
| iso-octane
| A hydrocarbon with an octane rating of 100. |
| isoblock
| A hard-rubber insulator block used for motor mounts. |
| isobutylene
| A refinery process petrochemical that is reacted with methanol to form MTBE or with ethanol to form ETBE. |
| isolate
| A technique where a component or system may be separated from the rest of the component or system without the los of fluids or pressures. |
| isolate, hold and dump
| Actions commanded by the ABS microprocessor to regulate hydraulic pressure to an individual wheel brake. |
| isolator
| A rubber or synthetic device used to separate two parts to reduce noise or vibration. |
| isolator pad
| A rubber or synthetic device used to separate two parts to reduce noise or vibration. |
| isomers
| Chemical compounds having the same molecular weight and atomic structure, but a different molecular structure. |
| ISP
| An acronym for an Internet Service Provider; a company that provides you access to the internet for a fee, the service provider gives you a software package, username, password, and access phone number. |
| ISS
| Idle speed solenoid or idle stop solenoid |
| ISV
| Idle speed valve |
| ITCS
| Ignition timing control system |
| ITPA
| An acronym for International Truck Parts Association. |
| ITR
| In-tank reservoir |
| ITS
| Idle tracking switch |
| ITVS
| Ignition timing vacuum switch |
| IVR Instrument Voltage Regulator
| An IVR is used to maintain constant voltage to thermoelectric gauges to maintain accuracy. |
| IVSV
| Idle vacuum switching valve |
Auto & Car Glossary
