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Manual Transmission

A manually shifted gearing device in the power train that allows variation on the relationship between engine speed and road speed.

Manufacturer

A person, or corporation engaged in the mass production or assembly of vehicles or any other product.

Manufacturer's Code

1. An alpha-numeric code to identify a product. 2. A lettered marking code on tire sidewalls indicating tire manufacturer, plant, tire size, type of construction, and date of manufacture.

Manufacturer's Service Manual

A book containing service information and technical data that is provided by the vehicle manufacturer.

Manufacturers Of Emission Controls Association (MECA)

A trade association of the manufacturers of emission-control systems and components.

Manufacturing

The science of planning, designing, managing, and scheduling people, goods, material, equipment, and machinery to produce a useable and sellable product.

MAP

[1] Manifold Absolute Pressure ie all pressures above below and at atmospheric found in the engines intake manifold [2] Following and plotting a circuit signal on an oscilloscope over a period of time.

MAP Sensor

A device used to measure MAP.

MAPPA

Manifold absolute pressure per altitude.

Marbles

Small pieces of dirt, rubber, or other debris on the outer edges of the race track, outside the racing line.

Marcel

The spring assembly in the clutch-drive plate that absorbs the energy when the clutch lever is released.

Margin

The amount a lender adds to the index on an adjustable rate mortgage to establish the adjusted interest rate.

Margin

The material between the face and head of an intake or exhaust valve.

Mark

1. One of the series of cars usually identified by a Roman numeral. 2. A term often mistakenly used for marque.

Markings

The identifying marks on an assembly or component.

Marque

A French term meaning "make," as in make of car.

Marriage

The installation of a vehicle's power train in its chassis on an assembly line.

MAS

An acronym for mass airflow sensor.

Masking

1. To cover up, as in prior to painting. 2. The modifying of intake ports with dams to redirect the air flow.

Masking Area

A preparation stage in a paint shop in which the parts that are not to be painted are covered with paper and held in place with masking tape.