Under the Hood: The Car Engine Quiz


By: Maria Trimarchi

6 Min Quiz

Image: shutterstock

About This Quiz

Do you know your alternator from your power steering pump? Would you know where to begin changing your own oil? Not everyone is mechanically inclined, but we're guessing that you know more than you think you know about your car's engine. It's impossible to be a driver without learning a few thing along the way!

Let's take a peek under the hood and find out what you know. We'll examine both the main body of the engine and all the components that attach. Does your expertise end at adding windshield washer fluid, or could you point out exactly where to find the timing chain? Car engines are both efficient and complex machines, with dozens of moving parts working together to power you down the road. Whether your car is diesel or gasoline driven, you should be able to recognize at least some of your engine's make-up!

Rev up your engine and let out on the clutch! As you shift your way through the questions, be sure you choose the answer that is correct to the best of your knowledge! Have no fear! You'll cruise through it without as much as a minor fender-bender! Let's put your knowledge to the test!

What's the function of the camshaft in your car's engine?

There is a shaft in internal combustion engines, like the one in your car, that uses elliptically-shaped lobes to control when the intake and outtake valves open and close. And that determines the engine's performance, peak horsepower and more.


Once your car's started, what supplies the car's electrical power needs?

Your car's alternator provides all the needed electrical power, including recharging the battery while you drive.


What's another name for the engine block?

An engine block is also called a cylinder block.


Having more of what makes an engine more powerful?

Engines with more cylinders are more powerful than engines with fewer cylinders.


Before the 1980s, what supplied the combustion chamber with fuel?

Today, cars use fuel injection to create the combustion needed in the combustion chamber. But before the 1980s, it was a carburetor that did the job.


What's it called if the cylinders in your car's engine are arranged in a straight line?

When an engine's cylinders are arranged in a straight line, it's called an inline engine.


Why are some engines called a V6 or V8?

Usually when an engine has more than four cylinders, those cylinders are divided into a V-shaped configuration of two cylinder banks, with three cylinders or more in each bank.


Which is not one of the three key things your car's engine needs to start and run properly?

Your car's engine needs a well-balanced air/fuel mixture, combustion and a spark to work properly.


What makes the spark?

Sitting above each of the engine's cylinders is a sparkplug. When you start your car, the ignition coil produces a spark that's distributed to the sparkplugs.


What does the spark ignite?

The spark ignites the air/fuel mixture.


After the spark ignites the air/fuel mixture, what happens?

That spark causes a small explosion that, in turn, pushes the pistons down. Now we're moving!


Pistons move up and down, and you can predict where they'll be during intake, compression, power and exhaust (known in a four-stroke engine as a four-stroke process). On intake, a piston is down. Is it up or down on the exhaust stroke?

The piston is up on the exhaust stroke, pushing the exhaust out.


What lubricates the cylinders in which the pistons move up and down?

All the moving parts inside your car's engine are lubricated with motor oil.


What's the purpose of radiator coolant (antifreeze)?

The car's cooling system, which includes the radiator, keeps the engine’s cylinder heads and valves cool by safely absorbing and dissipating heat, but it needs coolant and water to do so.


How often should you change your oil?

Oil changes are recommended for every 3,000 miles or 6 months, whichever comes first. However, many new cars can rely on an every 5,000 miles schedule.


Which is not considered an "extreme" operating condition?

You might think an "extreme" operating condition as very hot or very cold weather, or maybe if you're towing something heavy. Those are. But so is stop-and-go driving, only making short driving tips and never driving at high speeds on highways. Extreme conditions can change your oil change schedule.


How long can you prolong the life of your car's engine if you schedule regular oil changes?

Regular oil changes may help you get as much as twice the mileage from your engine than if you're nonchalant about it.


What powers your car's air conditioner?

The front of the crankshaft and the rear of the crankshaft have different duties. The front powers your car's accessories, including the air condition, the alternator and water pump.


What does the rear of the crankshaft power?

The rear of the crankshaft connects to the car's flywheel, providing power to the transmission (which, in turn, provides power to the car).


When you buy a car, it's "powertain" may be under warranty. What is a car's powertrain?

The car's powertrain includes all the components that make a car move, including the engine and drivetrain.


What's not part of a car's drivetrain?

A car's drivetrain includes all of the components needed to move the wheels, but not the car's engine.


What can help if your car's engine temperature begins to climb while you're driving?

Turn on the heat (and turn off the A/C) to help direct heat away from the engine. Don't rely on it as a fix though; an overheating engine needs to be checked out.


If you drive through high water on a flooded road, how could water get into the engine's combustion chamber?

Driving through high water could cause water to reach your engine's combustion chamber through the car's air intake system. Think you'll be crossing rivers in your vehicle? Consider a snorkel -- for the car, not you.


The energy your car's engine makes moving gears and wheels is called what?

This is called mechanical energy.


What's considered the "brain" inside your car's engine?

The camshaft is considered the brain inside your car's engine.


What does that mechanical energy become when the wheels, in turn, power the car?

The energy of the car as it goes down the road is called kinetic energy.


What controls the amount of air that gets into the engine?

The gas pedal controls the amount of air that will get into a car's engine.


Which is an example of an external combustion engine?

A steam engine, like on locomotives in the 19th century, is a good example. It relies on a boiler to heat water into steam, but because the combustion (the boiler) is outside the engine, it's an external combustion engine.


Engine timing belts can get dry, stretch out and deteriorate with time, wear and tear. It's recommended you change the belt (or chain) how often?

Experts recommend an engine's timing belt (or chain) be changed every 60,000 miles.


What's the ratio of air to fuel?

The fuel mixture is made up of way more air than fuel.


You hear a loud, medium-pitched knocking from your engine. What could it be?

Loud, medium-pitched knocking noises coming from under the hood could mean the bearings that support the engine's crankshaft are worn.


What keeps engine oil from leaking into the engine's combustion chamber?

Valve seals keep engine oil from leaking into the engine's combustion chamber.


Where are the proper lifting points for where to place a jack?

The lifting points are different from car to car. Any car with a frame, though, can be lifted with a jack by the frame.


Why might your car have dim headlights, but only intermittently and only while you're driving?

Dim headlights while you're driving is a good indication your car has a bad alternator. (Or you're hauling a really heavy load.)


Which was the most common car repair of 2015?

Replacing a bad oxygen sensor was the most common car repair among Americans in 2015. In second place, our cars needed catalytic converter replacements, and, third, replacement spark plugs. And all those loose fuel caps? Tightening them was the fourth most-common repair.


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