DICTIONARY OF AUTOMOTIVE TERMS - "Mi"

MIC
  1. Acronym for Mechanical Instrument Cluster
  2. Acronym for Microvan (e.g., Suzuki Carry).
Michelin X
Registered trademark for Michelin's steel belted radial cord tire.
Michigan Doubles
A combination vehicle consisting of a tractor pulling two trailers with a total of 11 axles, typically for hauling gravel(dump trailers) or steel (flatbed trailers).
Mickey mouse
A trivial thing. In automotive usage it means something that is simplistic and worthless.
Micro
One millionth part of unit specified.
Microbar
A pressure unit used in acoustics equal to 10-6 bar
Microbial corrosion
Corrosion associated with the action of micro-organisms present in the corrosion system
Microcar
Small car, popular in the 1950s, that featured a body offering full-weather protection and mechanics often derived from motorcycle technology, e.g., Goggomobil, BMW Isetta, etc.
Also See
Bubble car
Microcrystalline wax
Wax extracted from certain petroleum residues having a finer and less apparent crystalline structure than paraffin wax and having the following physical characteristics: penetration at 25°C (D1321)-60 maximum; viscosity at 99°C in Saybolt Universal Seconds (SUS); (D88)-60 SUS (10.22 centistokes) minimum to 150 SUS (31.8 centistokes) maximum; oil content (D721)-5 percent minimum.
Microfarad
Unit of capacitor electrical capacity equal to 1/1,000,000 farad. Written mfd or μf.
Micro finish
Degree of surface roughness, measured with a profilometer
Microgalvanic cell
Local cell
Microgroove
A small groove scribed into the surface of a solar photovoltaic cell which is filled with metal for contacts.
Micro-Inch
One millionth of an inch. Used in measuring imperfections of surface finishes. A measurement system used to express the roughness of a machined or ground surface.
Micrometer
  1. A precision measuring tool that will give readings accurate to 0.002 mm or 0.0001 of an inch. Sometimes called inside micrometer or outside micrometer. Also called a mike.
  2. A unit of measurement of thickness which is equal to one thousandth of a millimeter. Also called micron.
Also See
Air micrometer
Depth micrometer
External micrometer
Internal micrometer
Micrometre
See
Micrometer
Micron
Unit of length in metric system; a thousandth part (1/1000) of one millimeter.
See
Micrometer
Micron gauge
Instrument for measuring vacuums very close to a perfect vacuum.
Micro oil filter
A special oil filter designed to trap particles down to 1 Micrometer in order to allow extended oil change intervals in the order of 60,000 miles (100,000 km) without affecting engine life
Microphone
See
Bi-directional Microphone
Button Microphone
Carbon Microphone
Microprocessor
  1. Electrical component consisting of integrated circuits which may accept information, store it, and control an output device.
  2. A digital computer built on a single IC chip. It can perform arithmetic and control logic functions and is the basic component of any microcomputer system.

Microprocessor control unit
(MCU) an integral part of an electronically controlled feedback carburetor using a TWC catalyst. Various sensors monitor conditions. MCU is widely used on Ford vehicle for the control of air-fuel ratios
Microprocessor spark timing system
(MSTS)
Also see
Mapped ignition
Micro-surfacing
An overlay technique in which a machine mixes the oil and chips and then drops the mixture onto the road together. The mixture is used to fix ruts and as a surface treatment. Result offers skid-resistance for motorists.
Microsurfacing
A thin application of latex modified asphalt emulsion and sand is applied about 3/8" to 1/2" thick by a special truck-mounted paving system. The material sets and hardens within about one hour, and the road is then fully opened to traffic.
Microswitch
See
Throttle Microswitch
Midbed
In dual bed catalytic converters with air injection, the plenum between the three-way catalyst and the conventional oxidation catalyst, into which secondary air is injected
Middle body
See
Parallel middle body
Middle distillate
A general classification of refined petroleum products in the so-called middle range of refinery distillation that includes distillate fuel oil, Kerosene, heating oil, and diesel fuels.
Mid-engine
A chassis layout that positions the engine behind the passenger compartment but ahead of the rear axle.
Also See
Front engine
Rear engine
Underfloor mid-engine
Mid-engine chassis configuration
The engine is located in the center of the chassis directly behind the passenger compartment (normally these are only 2-seater vehicles) but ahead of the center line of the rear wheels. In most cases, the fuel tank is directly in front of the passengers. This provides much better weight distribution and handling. There are three basic chassis configurations used today. The front engine configuration with the engine in the front, the passenger compartment in the middle and the trunk in the back. There are rear-engineered cars (like the Volkswagen Bug and the Porsche 911) where the trunk is in the front, the passengers are in the middle and the engine is in the back, behind the center line. And the mid-engine configuration described above.
Also see
Mid-engine.
Midgrade gasoline
Gasoline having an antiknock index, i.e., octane rating, greater than or equal to 88 and less than or equal to 90. Note: Octane requirements may vary by altitude.
Also see
Unleaded Midgrade Gasoline
Mid-range
The middle of the rev range, around 3000 rpm
Midrange torque
The pulling power of the engine in the middle of the rev range
Midship section
A drawing showing a typical cross section of the hull and superstructure at or near amidships and giving the scantlings of the principal structural members
Mid-size car
  1. A passenger car with between 110 and 119 cubic feet of interior passenger and luggage volume.
  2. At one time (during the 1960s) a mid-size car was between the large Full-size car (like Cadillac, Lincoln, and Imperial) and the Compact cars (like Nova, Falcon, and Valiant). They included the Chevelle, Torino, and Coronet. However, with the fuel shortage of the mid-1970s, many models shrunk. For example, the full-size Mercury and Ford became about the size of the previous Torino. The Nova, et al, were called mid-sized in the '80s, especially with the introduction of the Chevelle, Escort, and Colt. By the close of the '80s, even Cadillac De Ville was smaller than the 1969 Chevelle.
Midsize SUV
Midsize SUVs became popular in the early 1990s as replacements for family sedans, station wagons, and minivans. There are many models of this type on the market today. The early models were based on a truck's ladder frames and live rear axles like the Ford Bronco and GMC Jimmy and are still evident in the Toyota 4Runner and Chevrolet TrailBlazer. Many of today's models have ironed out the stark features of those early models and have car-like characteristics.
Also see
Premium Midsize SUV
Midsize truck-type SUV
Chevrolet TrailBlazer Dodge Durango Dodge Nitro Ford Explorer GMC Envoy
Hummer H3 Isuzu Ascender Jeep Commander Jeep Grand Cherokee Kia Sorento
Mercury Mountaineer Nissan Pathfinder Nissan Xterra Toyota 4Runner Toyota FJ Cruiser

Midsize car-type SUV
Chevrolet Equinox Chrysler Pacifica Ford Edge Ford Taurus X GMC Acadia
Honda Pilot Hyundai Santa Fe Hyundai Veracruz Mazda CX-7 Mazda CX-9
Mitsubishi Endeavor Nissan Murano Pontiac Torrent Saturn Outlook Subaru Tribeca
Suzuki XL7 Toyota Highlander
MIG
Acronym for metal inert gas. A term used to describe gas metal arc welding
Migrate
When electrophoretic paint is attracted to car bodies when they are immersed in a bath of paint with an applied polarity across the bath and the bodies
MIG welding
An arc welding method in which the electric current is provided by the filler metal wire which is cooled and shielded from the access of air by a stream of chemically inert gas, thus preventing oxidation of the joint. Compare TIG welding
Mike
  1. A Micrometer.
  2. The use of a micrometer to measure an object.
MIL
Acronym for Malfunction indicator light
Also see
Circular Mil
Mild steel
A type of steel with a low carbon content (0.1-0.25%), widely used in vehicle construction.
Also see
Low-carbon steel
Mile
A distance of 1.609344 km
Also see
Nautical Mile
Revolutions Per Mile
Ton Mile
Vehicle Miles Traveled
Mileage
  1. The distance measured in miles, as by a mileometer.
  2. The total number of miles a motor vehicle has traveled.
  3. The number of miles a motor vehicle travels on one gallon of fuel.
Also See
Delivery mileage only
Fuel mileage
Special Mileage Tire
Mileage allowance
Mileage Allowance Lease agreements usually establish the average miles per year that the car may be driven during the lease. This is often between 12,000 and 15,000 miles. The lease contract also establishes the amount you'll have to pay for every mile driven over the allowance. This mileage fee is usually 15 cents per mile. You can often purchase additional miles at the start of the lease at a discounted rate. If you're sure you're going to drive more than the number of miles allowed, then your best option is to negotiate for a higher allowance on the lease.
Mileage counter
See
Trip mileage counter
Mileage tire
See
Special mileage tire.
Mile markers
Mile marker

Mile marker

Small green signs on United States highways which indicate the approximate number of miles from where the highway begins in a particular state at its most southern point (Mile zero) or at its most western point (Mile zero). The mile markers are also used to indicate exit numbers.

Mileometer
A device that records the number of miles traveled. Compare Odometer. Also spelled milometer.
Miles per gallon
(MPG)
  1. A measure of a vehicle's fuel efficiency. It is calculated by taking the total distance in miles divided by the number of gallons of fuel to cover the distance. Making the calculation after only a single trip can be deceptive since it may be difficult to get the same full tank each time. Thus, an accurate figure can better be obtained after several trips.
  2. The EPA certification for all vehicles in the subgroup for city driving, highway driving, and a blend of the two.
Miles per hour
A rate of speed where a multiple of the distance of 1.609344 km is covered in the time of one hour
See
Mph
Ton Mile Per Hour
Miles per tank
A deceptive measure of a vehicle's fuel efficiency as expressed by a distance in miles while using a portion of a tank of fuel. For example, "I drove to the airport and back on only half a tank of fuel." Both the exact distance and the actual amount of fuel are vague; but the impression is given that the vehicle gets really good miles per gallon.
Milestone Car Society
P.O. Box 50850, Indianapolis, IN, 46250.
Milestone cars
Great cars of the post-war era, 1946-70 which include the following:
Military use
Includes sales to the Armed Forces, including volumes sold to the Defense Fuel Supply Center (DFSC) for use by all branches of the Department of Defense (DOD).
Milk run
A bus route with frequent delivery stops
Mill
  1. Often used to refer to the whole engine.
  2. To remove metal through the use of a rotating toothed cutter.
  3. To grind, press or reduce to powder.
  4. To shape or cut metal.
  5. A Milling cutter
  6. A Milling machine
Also see
Bar Mill
Batch Mill
Billet Mills
Blooming Mills
Boring Mill
Milled from bar
A fastener made on a screw machine or lathe by cutting material away from the original piece of metal. It is used for manufacturing very large diameters which cannot be cold formed and for small quantities where it would not be economical to set up cold forming equipment. However, machining can interrupt the grain of metal causing a lessening in tensile and fatigue strength. Also called machining.
Milled glass fiber
Chopped strands of glass fibre which vary in length from 3 mm to about 50 mm
Miller cycle
A type of engine developed by Ralph Miller in the 1940s. It differs from a standard engine in that it has a supercharger. During the compression stroke, the intake valve remains open so that compression is against the supercharger instead of against the walls of the cylinder. The efficiency of the engine is increased by up to 15%.
Milli
Combining form denoting one thousandth (1/10001; for example, millivolt means one thousandth of a volt.
Milliampere
One thousandth of an ampere. With figures it is usually written mA
Milliammeter
An ammeter with a milliampere scale
Milligram
A unit of measurement of weight. A thousand milligrams equal one gram. With figures usually written mg
Milliliter
A unit of measurement of liquid or volume where a thousand milliliters equal one liter. Also, one milliliter equals one cubic centimeter. With figures usually written ml.
Millilitre
British spelling of Milliliter
Millimeter
A unit of measurement of distance where a thousand millimeters equal one meter. 25.4 millimeters equal an inch. With figures usually written mm.
Millimetre
British spelling of Millimeter. A metric measurement equivalent to about 0.039370 of an inch.
Milling
See
Thread Milling
Milling cutter
A rotating, toothed cutter in a Milling machine, used to cut or shape metal
Milling machine
  1. A machine that uses a variety of rotating cutter wheels to cut Splines, gears, Keyways, etc.
  2. A machine tool with a table on which rests material which is cut by a rotating cutting tool held by a horizontal arbor or vertical spindle
Milling Process
A machining process whereby a surface is generated with a rotating toothed cutter. Each tooth takes an individual chip.
Millsaw file
A flat hand file with round or square edges for sharpening saw blades or machine-cutting knives
Milometer
A device that records the number of miles traveled. Compare Odometer. Also spelled mileometer.
MIL
Acronym for Mechanic Installed Market.
Mine Drainage
See
Acid Mine Drainage
Mineral
Any of the various naturally occurring inorganic substances, such as metals, salt, sand, stone, sulfur, and water, usually obtained from the earth. Note: For reporting on the Financial Reporting System the term also includes organic non-renewable substances that are extracted from the earth such as coal, crude oil, and natural gas.
Mineral oil
A light lubricating oil refined from crude oil
Minerale
See
Liquide Hydraulique Minerale
Minerva
A vehicle brand of which all 1925-48 models except 4-cyl are Classic car.
Mini
A small British front-wheel drive car designed in 1959 by Sir Alec Issigonis (1906-88). Current model is the Cooper (2002-07). Also spelled MINI.
Miniature offset open-end wrench
A very small, open-ended wrench with two jaw openings of the same size set at different angles to the handle, e.g., 15° at one end and 60° at the other. Also called Electrical wrench
Minibus
Small, single-decker bus designed to carry around 12-20 people
Minicar
A very small sedan carrying no more than four adults
Mini catalytic converter
A small but usually a primary catalytic converter which is installed close to the engine in the headpipe
Miniframe
See
Suspension subframe
Mini-grinder
See
Angle grinder
Minilite
A true magnesium wheel, developed for the Mini in 1962 by nuclear engineer Derek Power on the basis of experience gathered with magnesium components in nuclear power plants. The Minilite started the boom in alloy wheels
Minilite alloy wheel
A true magnesium wheel, developed for the Mini in 1962 by nuclear engineer Derek Power on the basis of experience gathered with magnesium components in nuclear power plants. The Minilite started the boom in alloy wheels
Mini-motorhome
See
Type C motorhome
Minimum ignition Time
The minimum allowable time for the specified function of any device.
Minimum stable signal
(mss) Correct setting for an expansion valve where it is utilizing the evaporator efficiently but remains free from hunting.
Mini spare wheel
See
Space saver spare.
Minimum thickness
The least amount of thickness to which a brake disk can be machined or worn before it becomes unsafe. This dimension is usually stamped or cast into the disc.
Mini tube cutter
A compact tube cutter for cutting brass, copper, plastic, or thin steel tubing in confined areas
Minivan
  1. Minibus-sized van with no side windows, used to transport goods instead of people.
  2. Although the smaller van, with windows, was available from VW and its GM copy Greenbrier (based on the Corvair), the term was not known until 1983 when Chrysler produced its Magic Wagon series (later copied by GM and Ford) which has almost eliminated the station wagon.
Minlon
A mineral-fiber-reinforced polyamide, used for alloy wheels as a rim trim cover that protects the balancing weights
Min/max governor
Controls the idle speed and prevents overspeed
Minor diameter
  1. The inside or smallest diameter of the screw threads.
  2. The diameter measured from the thread valley to the corresponding valley on the opposite side of the bolt or screw
  3. On a straight thread, the minor diameter is the diameter of the coaxial cylinder which would pass through the roots of an external thread.
Minority carrier
A current carrier, either an electron or a hole, that is in the minority in a specific layer of a semiconductor material; the diffusion of minority carriers under the action of the cell junction voltage is the current in a photovoltaic device.
Mint condition
A colloquial term for a vehicle that has been kept in, or restored to, perfect condition. Also called cherry condition.
Mirror
A reflective device which is located in one of several positions between the two A-posts within the passenger compartment (called the Rearview mirror); behind either/both sunvisors (Vanity mirror); on either side of the outer A-posts; on the forward or leading edge of the front Doors; or on the front Fenders.
Also See
Anti-dazzle mirror
Day-night mirror
Dimming mirror
Dipping mirror
Door Mirror
Driving mirror
Electric mirror
Exterior mirror
External mirror
Fender Mirror
Inspection mirror
Interior mirror
Rearview Mirror
Remote mirror
Vanity mirror
Wing mirror
Mirror control
See
Remote mirror.
Misalignment
  1. General term referring to all types of frame damage caused by accidents.
  2. The condition of two mating parts which are not placed in proper alignment
MISAR
Acronym for Microprocessed Sensing and Automatic Regulation (GM)
Miscellaneous petroleum products
Includes all finished products not classified elsewhere (e.g., petrolatum lube refining byproducts (aromatic extracts and tars), absorption oils, ram-jet fuel, petroleum rocket fuels, synthetic natural gas feedstocks, and specialty oils).
Miscibility
Substances that are capable of being mixed.
Misfire
The failure of the fuel charge in one or more engine Cylinders to fire or ignite at the proper time. It can be due to poor Compression caused by worn or improperly adjusted valves, worn Piston rings, a faulty Head gasket, or in the case of a Two-stroke engine leaking crank seals. It can also be caused by poor Ignition due to worn or dirty Spark plug Electrodes, worn or improperly gapped points or spark plugs, poor fuel delivery, faulty ignition wiring, or faulty Distributor components. An easy way to detect the problem is to put a stiff piece of paper at the end of the Tail pipe and listening for an irregular puffing sound. Also called missing or backfiring.
Misfiring
Failure of an explosive to occur in one or more cylinders while engine is running. This may be a continuous or intermittent failure
Miss
See
Misfire
Missing
See
Misfire.
Mist
See
Spray mist
Mist action
An action of intermittent wipers which will make one or two swipes to clear away any mist from the windshield.
Mist coat
Usually the final color Coat, produced by over-reducing with a slow evaporating Thinner. It is generally used to blend in the final Overlap areas.
Misting
The fog sometimes produced during adhesive, coating, or sealer spray application is usually caused by excessive atomizing pressure. Most common when spraying water-dispersed products of very thin consistency or slow drying materials such as diluted house paint.
Mitsubishi
Mitsubishi

Click image for books on
Mitsubishi

A model of automobile manufactured in Japan by the Mitsubishi Motors and includes 3000GT (1991-99), Aspire (1999-2003), Cordia (1982-90), Diamante (1992-2004), Eclipse (1990-2008), Endeavor (2004-07), Expo (1992-95), Galant (1969-1975), Galant Sigma (1976-90), Galant Eterna (1987-98), Grunder (2004-current), Lancer (2002-08), Legnum (1999-2003), Minivan (1988-90), Mirage (1978-2002), Montero (1982-2006), Montero Sport (1997-2004), Outlander (2003-07), Pickup (1988-96), Precis (1985-94), Raider (2006-07), Sigma (1989-90), Starion (1982-90), and Tredia (1982-90)

Mix air cap
See
External mix air cap
Internal mix air cap
Mixed-flow impeller
A pump impeller which combines radial and axial-flow principles, i.e., liquid flows both along the drive shaft and out through the impeller; pump impellers are classed as mixed-flow when the specific speed is 2,000 to 6,000 rpm
Mixed-flow pump
A centrifugal pump which develops its head partly by centrifugal force and partly by the lift of the vanes on the liquid
Mixer
The combination of Mixer head, Mixer throat, and Mixer tube
Also see
Balanced Mixer
Banbury Mixer
Static Mixer
Mixer face
The air inlet end of the mixer head.
Mixer Head
The portion of an injection (Bunsen) type burner, usually enlarged, into which primary air flows to mix with the gas stream.
Mixer Throat
The portion of the mixer which has the smallest cross-sectional area and which lies between the mixer head and the mixer tube.
Mixer Tube
The portion of the mixer that lies between the throat and the burner head.
Mixing chamber
  1. That part of the welding torch where the welding gases are intimately mixed, prior to combustion.
  2. That part of a carburetor distinct from the float chamber both in function and layout, in which the air and the fuel mix as they meet.
  3. The Midbed of a catalytic converter
Mixing head
The head of an oxyacetylene torch by which the mixture of oxygen and acetylene can be adjusted
Mixing rolls
A machine designed for the mixing and Mastication of the materials from which tires are made
Mixing Well
See
Main Mixing Well
Mix-master
Trucker slang for a highway cloverleaf as in "You got a parking lot on the mix-master up ahead."
Mixte frame
A BicycleFrame that replaces the Top tube with twin lateral tubes that run all the way from the Head tube back to the rear Dropouts.
Mixture
  1. A substance made up of two or more chemicals in some proportion.
  2. A Fuel-air mixture in an internal combustion engine.
  3. The combination of oil and gasoline in the fuel tank of a two-stroke engine, e.g., 150, i.e., one part of oil is added to every 50 parts of fuel.
Also See
Azeotropic Mixture
Fuel-air mixture
Fuel mixture
Idle mixture screw
Idle mixture
Lean air-fuel mixture
Lean mixture
LP Gas-Air Mixture
Main mixture discharge nozzle
Rich air-fuel mixture
Rich mixture
Mixture Control
See
Automatic Mixture Control
Mixture control knob
See
Choke
Mixture control screw
See
Idle mixture screw
Mixture control solenoid (M/C Solenoid)
  1. A device, installed in carburetor, which regulates the air/fuel ratio by oscillating the metering rods.
  2. A computer-controlled device in a feedback carburetor that alters the mixture adjustment by moving the carburetor's metering rod in and out of the metering jet. Also called a Duty-cycle solenoid
  3. An electronically controlled device which regulates bleed air, fuel, or both, on carbureted vehicles.
Mixture control unit
  1. A unit in the K-jetronic fuel injection system which combines the fuel distributor and the airflow sensor; it monitors the rate of airflow and meters the fuel supplied to the injectors.
  2. In Bosch CIS, the collective term for the airflow sensor plate and the fuel distributor, which are integrated into a single component
Mixture discharge nozzle
See
Main mixture discharge nozzle
Mixture screw
See
Idle mixture screw.
Mixture volume
The quantity of air/fuel mixture