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BARO Read Solenoid

The output control device used on some Chrysler vehicles to dump the vacuum applied to the MAP sensor to update the barometric pressure reading through the MAP sensor range

Barometer

An instrument used for measuring barometric pressure.

Barometric Pressure (BARO)

The pressure exerted by the weight of the earth's atmosphere, equal to one bar, 99.97 kPa, or 14.5 psi at sea level. Barometric pressure changes with the weather and with altitude. Since it affects the density of the air entering the engine and ultimately the air/fuel ratio, some computerized emissions-control systems use a barometric pressure sensor so that the spark advance and exhaust gas reticulate (EGR) valve flow can be regulated to control emissions more precisely.

Barometric Pressure Sensor

A device that senses barometric pressure and sends an electrical signal to the CPU for optimum engine control.

Barrel (bbl)

1. A term sometimes applied to the cylinders in an engine. 2. A term used to refer to the number of throttle bores in a carburetor.

Barrel Faced Ring

A compression piston ring with a rounded contact face.

Barrel Finish

The rounded surface on a piston skirt.

Barrel Hose

A hose constructed with a special liner to prevent refrigerant leakage through its walls. Most air-conditioning systems in vehicles manufactured after 1988 have barrier-type hoses.

Barrel Roll

A vehicle rollover, sideways.

Barrier

1. A term given to something that stands in the way, separates, keeps apart, or restricts; 2. A term for a diode or transistor junction 3. an obstruction

Barrier Charge

The potential developed across a semiconductor junction.

BART

Best Available Retrofit Technology (emissions related)

BAS

An European acronym for Brake assessment System

Base

[1] The name for the section of a transistor that controls the current flow through the transistor. [2] The unique number of values in a numbering system; decimal has 10, binary has 2, hexadecimal has 16.

Base 10

A base unit in the metric system. All metric units are increased or decreased in units of 10. One meter, for example, has 10 decimeters, 100 centimeters, or 1,000 millimeters.

Base Circle

The low portion of each cam on the camshaft, concentric with the journal, which is not part of the lobe.

Base Coat

The initial layer of paint.

Base Current

The amount of current that flows through the base-emitter section of a transistor

Base Idle

[1] Manufacturers recommended idle speed [2] The RPM that the IAC solenoid attempts to maintain

Base Ignition Timing

The specification for the number of degrees before top dead center the ignition is fired without advance of any kind