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Inspect

To examine a component or system for any audible or visual signs of a defect.

Inspection

The process of measuring, examining, testing, gauging, or otherwise comparing the unit with the applicable requirements or specifications.

Inspection Maintenance (I/M)

The periodic and systematic inspection and maintenance of a vehicle's ignition, fuel, and emissions-control systems, commonly used to refer to state / county emissions inspection and testing programs.

Install

To set up an accessory part or kit for use in a vehicle.

Installed Height

The distance from the valve-spring end to the valve-spring seat.

Instant Center

An imaginary center point around which a wheel appears to pivot.

Instrument Panel

A grouping of indicator lights and gauges designed to inform the driver of curent vehicle operations.

Insulated Return System

The ground wire of a two-wire electrical system.

Insulation

Any material that blocks the flow of electricity. Any material containing more than 4 electrons in its valance shell.

Insulation Tape

Tape (usually cork) used to wrap refrigeration hoses and lines to prevent condensate drip.

Insulator

1.A material with high electrical resistance that supports or separates conductors to prevent undesired flow of current to other objects. 2. A material that contains less than four electrons in its valance shell.

Insulator Ribs

In a spark plug, unevenly spaced circular ridges on the upper section of the insulator to reduce or prevent flashover of the high voltage from the terminal to the lower shell.

Insurance Information Institute

A public information and communications association.

Insurance Institute For Highway Safety

A highway and vehicle safety research organization.

Intake

The point at which a fluid or gas enters a pipe or channel. The act of taking in.

Intake Air Temperature Sensor

(IAT) A thermistor device that senses intake air temperature by changing it's resistance as a negative temperature coefficient resister.

Intake Manifold

A metal component used to duct 1. The air/fuel mixture from the carburetor to the intake parts. 2. Air in an injected engine to the intake ports.

Intake Over Exhaust (IOE)

An engine design having intake valves in the cylinder head and exhaust valves in the block.

Intake Ports

1. Passages in the cylinder head that direct air/fuel mixture from the intake manifold to the intake valves. 2. Passages in an L-head engine block that direct the air/fuel mixture from the intake manifold to the intake valves. 3. Passages in the head or block of an injected engine that direct air to the intake valves from the intake manifold.

Intake Stroke

A downward stroke of a piston that draws the air/fuel mixture into the cylinder.