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High-tension Cables

A term used for spark plug wires.

High-tension Wire

The wire that transmits high voltage from the coil to the distributor.

High-top

See high-rise.

High-vacuum Pump

A two-stage vacuum pump that has the capability of pulling below 500 microns (0.009 psia or .066 kPa).

High-voltage Cables

The secondary cables that carry high voltage from the distributor to the spark plugs.

Highboy

A hot rod that has not been chopped, channeled or sectioned.

Higher Heating Value (HHV)

The measure of the heat that is released when a fuel is burned.

Highway Loss Data Institute (HLDI)

A research organization sponsored by the property-casualty insurance industry.

Highway Users Federation (HUF)

A transportation coalition dedicated to preserving freedom of choice in transportation and mobility.

Hign Tension Voltage

Voltage which is high enough to enable current to jump across the spark pulg gap.

History

Something that is damaged or destroyed beyond repair.

History Code

A history code is set when a monitor tests fails during a trip, however additional trips shoes no continued failure. A history code is stored in memory for 40 warmup cycles.

Hitch

A device that is attached to the rear of a vehicle to allow it to pull a trailer.

Hitch Ball

A steel sphere mounted on top of the hitch to receive the cup-like fitting of a trailer.

Hitch Ball

The round mount to which a trailer tongue attaches in most towing applications (excluding those that use a fifth-wheel hitch). Balls come in several different sizes; the most common are 1 7/8, 2 and 2 5/16 inches. In some cases, the ball is permanently attached to a truck's bumper. In other cases, the ball is attached to a hitch or drawbar that plugs into the vehicle's receiver. A time- and aggravation-saving device for consumers who tow different trailers on a regular basis is a multi-ball hitch, which features several different-size balls and can be adjusted up and down to align the tow vehicle with various trailer tongue heights. Also known as utility ball mount.

Hitch Cover

See hitch plug.

Hitch Pin

A term used for hitch receiver.

Hitch Plug

A restyling product that plugs into a trailer hitch receiver when the vehicle isn't towing. Hitch plugs come in a tremendous assortment of styles, ranging from sports team logos to automotive logos. There are plugs designed to appeal to golfers, boaters, hunters and various other enthusiasts, too.

Hitch Receiver

A heavy square tube into which the removable shank supporting the hitch ball is inserted.

Hitch Weight

The load imposed to the tow vehicle's hitch by the trailer tongue, not to exceed 10-15% of the gross trailer weight.