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The Spokesman-Review Newspaper
Spokane, Washington  Est. May 19, 1883

To speak car talk, learn lingo

Bill Love Marketing Department Columnist

There is plenty of special terminology in the automotive realm. Knowing some of it can help you know your car a little better. For a start, here’s a glossary listing with an entry for each letter of the alphabet.

A-pillar: The structural support on either side of the windshield, just ahead of the doors.

B-pillar: The structural support just behind the front door. Hardtop models don’t have this support, hence the term “pillarless hardtop.”

C-pillar: The structural support just behind the rear door, supporting the rear of the roof.

Diagnostic code: A “trouble” code, usually a two-digit number, that technicians retrieve with a scanner to aid in diagnosis. Generally, a check engine light illuminates to alert the driver that there are codes in storage, indicating a malfunction.

ECM: An acronym for Electronic Control Module, an on-board computer that controls engine management, diagnostics, fuel delivery, and emissions.

Fifth wheel: A coupler mounted on the back of a truck used to connect a semitrailer; also mounted in the back of heavy-duty pickups to connect a travel trailer. The coupler allows for side-to-side movement of the trailer, as well as up and down.

GVWR: An acronym for Gross Vehicle Weight Rating. Refers to the maximum amount a vehicle should weigh with passengers, cargo and fuel.

Hydroplane: The phenomenon of a tire rolling on a layer of water on the road surface rather than making contact with the pavement. Occurs when there is insufficient tread, too much water, or both, and the water can’t be displaced fast enough from under the tire.

Injector: A nozzle used to deliver fuel to the engine in an atomized spray pattern — same as fuel injector.

Jet: A specific sized orifice in a carburetor used to meter fuel flow.

Knock Sensor: An engine sensor that tells the ECM when spark knock is detected, momentarily retarding ignition timing until detonation ceases.

Lexan: The trade name for a shatterproof clear plastic used in many modern headlamp system assemblies.

Macpherson Strut: A type of front suspension where the shock absorber is mounted beneath the coil spring.

Nitrous Oxide: An explosive gas (N2O) mixed with gasoline to increase the efficiency of combustion and raise horsepower.

Oxygen Sensor: A sensor in the exhaust used to measure completeness of combustion, signaling the ECM to adjust fuel delivery accordingly.

PCV Valve: PCV is an acronym for Positive Crankcase Ventilation. The device is a one-way valve that allows for the recycling of crankcase fumes.

Quarter Panel: A welded-in panel usually at the rear sides of a vehicle. Sometimes referred to as a fender, in error, as fenders are bolted on. A front “fender” is actually a quarter panel if welded on, for example on a Karmen-Ghia.

R-134A: A CFC-free air conditioning refrigerant used in most modern vehicles.

Supercharger: A compressor (usually belt driven) used to force-feed air to an engine.

Turbocharger: An exhaust gas driven “supercharger” with turbine-like design.

Undercarriage: The chassis of a vehicle.

Viscosity: The resistance of a fluid to flowing.

Wheel Base: The distance from the center of the front wheels to the center of the back wheels of a vehicle.

Xenon: An element that is a gas at room temperature — used in making bright white automotive lamps.

Y-pipe: A y-shaped exhaust pipe that merges two passages into one — many Subaru owners have learned about these.

Zerk fitting: A nipple-like lubrication fitting through which grease is applied to a chassis or suspension joint.

There you have it — use some of those terms around the car-types, and it might seem as though you know what you are talking about.

•Readers may write to Bill Love, c/o The Spokesman-Review Auto Section,

P.O. Box 2160, Spokane, WA 99210. Or you may contact him via e-mail at precisiondriving@spokesman.com.