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Light The Weenies

Same as light the rugs.

Light Up

To perform a burn out.

Light-duty Vehicle

Any motor vehicle rated at 8,500 pounds (3,856 kilograms) GVWR or less, having a curb weight of 6,000 pounds (2,722 kilograms) or less, and having a frontal area of 45 square feet (4.2 square meters) or less.

Light-off, Mini-oxidation Catalytic Converter

A small catalyst mounted just behind the exhaust manifold that gets hot very quickly after the engine is started, so that it begins working in time to neutralize much of the extra pollution that is produced during cold running.

Lights

The timing lights at the end of a drag strip.

Lightweight Leaf Spring

A fiber-composite spring.

Lightweight-skin Spare Tire

A bias-ply, compact spare tire with a reduced tread depth to provide about 2,000 miles (3,218 kilometers) of trad life; designed for emergency use only, and driving speed limited to 50 mph.

Lime Deposits

A condition that exists in a cooling system when the lime, present in water-based coolants, comes out of solution and coats the engine's water passages.

Limited-production Option (LPO)

An item of new car equipment available for a limited market, such as a high-performance police package.

Limited-slip Differential

A differential having special friction mechanisms tending to keep both rear-axle shafts rotating at the same speed, regardless of unequal tire-to-road surface friction.

Limited-slip Differential Gear Oil

A specially formulated gear oil required in limited-slip differentials because of the extreme pressures on the clutch cones or clutch plates and discs.

Limiting Valve

A term used for front-axle limiting valve.

Limits

The maximum and minimum values designated for a specific element.

Limo

Short for limousine.

Limousine

1. A chauffeur-driven formal sedan having a glass partition separating the driver from the passengers. 2. A bus or van used to carry people to and from an airport or bus station.

Limp In Mode

A driveability condition where the Logic Module has recorded a fault in the on-bord computer system and has substituted a known value for the failed input. When this occures, driveability characteristics are greatly affected, but will allow the operator to get to a repair facility.

Limp-In Mode

This term is used by many manufacturers to explain the driveability characteristics of a failed computer system.

Line Contact

1. The contact made between the cylinder and the torsional rings, usually on one side of the ring. 2. The contact made between the valve and the valve seat.

Line Job

Beating a drag competitor from the start.

Line Mechanic

1. A mechanic who works on the repair line at a dealership. 2. A mechanic who is skilled in a particular automotive system.