Learn the Meaning of Common Auto Shop Lingo

Have you ever taken your car to a mechanic/dealership and not been too sure what exactly they are saying? In the automotive world this happens quite a lot. Non-car people aren’t that bothered with car terms most of the time, but a lot of them wish they knew more because they do occasionally come in handy. Here are some of the most common auto shop terms it doesn’t hurt to know.


In auto insurance terms, it refers to original components on your car being replaced with new ones, usually improving the car’s condition. Sometimes insurers may ask for you to contribute to the cost since the new parts add value to your car.


Parts made by companies which are not the original manufacturer. Good aftermarket components usually exhibit a quality that meets or surpasses that of the original manufacturer.


Original equipment manufacturer. Basically a part which comes straight from the factory of your car’s respective manufacturer and was specifically designed for it.

Beltline (Waistline)

It’s the line formed by the lower edges of all the windows on your car. Effectively, it separates your car into a top and a bottom half.


Rear-wheel drive, front-wheel drive, and all-wheel drive. Essentially, where the power from the engine is sent. If it’s a rear-wheel drive car, the rear wheels propel you. If it’s a front-wheel drive, the fronts do, etc.

Torque Steer

If your car is FWD and the steering wheel starts turning when you give it a lot of throttle, you’re experiencing torque steer. Because the front wheels have to deal with turning and propelling the car forward, a lot of power can sometimes overwhelm them.


It’s also referred to as detonation. It occurs when leftover fuel/air in the combustion changer randomly explodes after the spark plug has fired. If you notice a knocking noise take your car to a mechanic because it decreases the engine’s lifespan drastically.


It stands for naturally aspirated, i.e. an engine which doesn’t use a turbocharger or a supercharger to force more air into the engine.


The closest inner part of a corner. It’s usually the quickest way through a corner and the most effective way.

Fast idle

This is when the idle speed increases for a short time after a cold engine starts, which occurs to improve drivability and to help the engine warm up more quickly.

Fuel injection (FI)

A fuel delivery system where nozzles, also called injectors, push gasoline into the intake manifold or cylinders, which allows for more exact fuel control and better fuel efficiency. There are many forms of fuel injection, but almost all modern vehicles use electronic fuel injection.


This refers to the momentary loss of power that occurs at initial acceleration.


This is what we call the degree of “looseness” in a movable component or series of components. This term is most commonly used in reference to suspension or steering wear. When speaking about steering, play is the amount of free movement that you feel in the wheel before the vehicle wheels actually begin to turn.


This happens when a vehicle steers itself, on its own, to one side or the other when driving or braking. This can be a tell-tale sign of the need for a wheel alignment.

These are some of the most basic automotive terms that everyone can benefit from learning. There are a ton more terms used commonly among mechanics, and we have just scratched the tip of the iceberg! Hopefully this helps you to be more knowledgeable in your conversations about your vehicle.