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Distributor Rail

A term used for distributor pipe.

Distributor Timing

A term used for ignition timing.

Distributor Vacuum Advance

A term used for vacuum advance.

Distributor Vacuum-advance Control Valve

A term often used for deceleration valve.

Distributor-less Ignition

A term used for distributor-less ignition system.

Distributor-less Ignition System

An ignition system that relies on a computer to distribute the electrical spark to the proper spark plug.

Distributorless Ignition System

Abbreviated DIS. A late-model ignition system that does not use a distributor. Instead, the engine management computer tells the coil (or coils) when to fire.

Diurnal Effect

The diurnal effect deals with the heating and cooling of gasses, there expansion and retraction in proportion to there temperature.

Div

An abbreviation for division.

Dive

The tendency of the front of a vehicle to press down on the front springs during heavy braking.

Divergent Nozzle End

An exhaust-pipe nozzle end that expands from the inlet to the end.

Divergent-convergent Nozzle End

An exhaust-pipe nozzle that is expanded then reduced in size at the end.

Diverter Valve

A vacuum-operated valve in an air-injection system that directs air-pump output to the atmosphere during high-vacuum deceleration to eliminate backfiring.

Division

1. A branch or department of an organization. 2. The mathematic operation to determine how many of one number is contained in another; for example, how many 10s are in 100.

DIY

An acronym for do-it-yourself.

DIYer

An acronym for a do-it-yourselfer.

Dizzy

Slang for distributor.

DJP

Acronym for Diagnostic Junction Port (Chrysler)

DKV

Deceleration kick valve.

DLC

An acronym for Data Link Connector formerly referred to as the ALDL or assembly line communications link, this is the connector to which the diagnostic scan tools are connected.