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About This QuizIt's under the hood of every car, truck and SUV, but how many people really know how one works? Do you know a spark plug from a fuel injector?
A car engine's job is to:
convert fuel into heat
convert fuel into motion
There's a lot of heat in a car's engine -- and a lot of exhaust coming out of it -- but these are byproducts of the engine's true purpose. An engine has to use fuel to create motion to move the tires.
convert fuel into exhaust
A car uses a four-stroke engine. The four strokes are:
intake, compression, combustion and exhaust
In the intake step, a cylinder gets some fuel and air to burn. Then, it compresses the fuel to make the combustion step (the explosion) more powerful. In the last step, the cylinder releases its exhaust.
injection, rotation, combustion and exhaust
injection, carburetion, rotation and exhaust
A device that works on the same principle as a car engine is:
a nuclear submarine
a giant robot
a spud gun
In a both spud gun and a car engine, you ignite a small amount of fuel, releasing a large amount of energy. (And it's equally unwise to get in front of a moving car or a loaded spud gun.)
A crankshaft's job in an engine is to:
deliver fuel to the cylinders
change linear motion into rotational motion
When gasoline ignites in a cylinder, the piston moves in a straight line. Your wheels, on the other hand, need to turn. The piston moves a connecting rod, which turns the crankshaft, producing the rotational motion.
keep cylinder heads in place
A timing belt or timing chain links these two components together so that the valves are in sync with the pistons:
the flywheel to the camshaft
the crankshaft to the camshaft
A timing belt or timing chain links the crankshaft to the camshaft so that the valves are in sync with the pistons.
the cylinder head to the camshaft
There are three basic failures that can happen in an engine: bad fuel mix, lack of compression and:
lack of exhaust
lack of water
lack of spark
Lots of things can go wrong under the hood, but the big three in the engine involve fuel, compression and fire .
In a car engine's cylinder, valves let fuel in and exhaust out. The ______ moves these valves.
A camshaft is a rotating rod that uses a series of lobes to open and close the valves. Most modern engines have overhead cams -- the camshaft is directly above the valves.
A turbocharger is:
a set of gears that makes the wheels turn faster
a turbine that compresses the air traveling into the engine
Turbochargers and superchargers are both air compression systems. They pressurize the air moving into the engine, increasing the engine's power.
an injector that delivers fuel to the engine faster
When you turn the key to a car, the starter motor:
sends electricity to the spark plugs, starting ignition
sends electricity to the fuel pump, forcing the car to start
spins the engine a few revolutions, starting the combustion process
The starter motor has a big job -- it has to overcome friction, cold weather and other factors to get your engine started. If it fails, nothing happens in the engine when you turn the key.
When a car's engine is running, power to operate the radio, CD player, headlights and windshield wipers comes from the:
A large battery is used to start the engine when you turn the key; however, once the engine is running, power for the car's accessories comes from the alternator. The alternator is connected to the engine by a belt and generates electricity to recharge the battery, too.
Modern cars use internal combustion engines, but some early models used external combustion engines. What is one example of an external combustion engine?
Steam engines were most commonly used in trains and boats, but did power some types of cars.
Why don’t we use steam engines for cars anymore?
They set off too many smoke alarms.
They smelled too bad.
They aren’t as efficient.
Internal combustion engines are a lot more efficient than external combustion engines, which is why steam engines fell out of favor for cars.
What’s another name for the four-stroke engine cycle?
The Otto cycle is named after its inventor, Nikolaus Otto.
What are the three common ways to arrange an engine’s cylinders?
V-6, V-8, HEMI
inline, V, flat
An engine’s cylinders are most often arranged in a line (inline), in two rows set at an angle (V) or in two opposite banks (flat).
inline, flat, rotary
What might happen if water gets into your gas tank?
It’ll make it hard for the engine to burn the fuel.
Water will prevent the gasoline in the system from burning properly, which will cause combustion problems in the engine, which will prevent the car from starting or cause it to run poorly.
It’ll help the car get better gas mileage.
It’ll make the engine blow up.
What happens if your car leaks or burns off all of its oil?
It’ll start an oil fire.
The engine will seize.
Oil lubricates the pistons so they can move smoothly inside the engine, and without oil, the engine will seize.
It’ll cause oil poisoning.
What are the two main components of the engine cooling system in most cars?
air intake and turbocharger
battery and fan
radiator and water pump
With a water-cooled engine, which is the most common type of cooling system, the radiator and water pump circulate water to absorb heat and move it away from the engine.
Which of these cars features a popular example of an air-cooled engine?
the Tesla Model S
the Volkswagen Beetle
The Volkswagen Beetle was designed with an air-cooled engine specifically for its simplicity.
the Ford Model T
Which of the following commonly uses air-cooled engines?
Many motorcycles are powered by air-cooled engines.
Oscar Mayer Wienermobiles
What are the three common ways to deliver fuel to an engine?
carburetion, hybridization, electrical charging
fuel injection, infusion, circulation
carburetion, port fuel injection, direct fuel injection
Carburetion, port fuel injection and direct fuel injection all get the fuel where it needs to go.
Why does a diesel engine get better mileage than a gasoline engine?
because of coal rolling
because it contains more energy
Diesel has a higher energy density than gasoline, meaning that each gallon burned makes more power.
Actually, it doesn’t.
What is the steam engine’s main advantage?
It’s easy to fix.
It can use anything as fuel.
A steam engine just needs to create steam, so it can burn anything as fuel. That's why in those old silent movies, when the hero runs out of coal to power the train, he starts burning his coat and hat.
Steam pollutes less.
What are two of the main advantages to a 4-cylinder engine?
It’s efficient and compact.
The 4-cylinder engine did not become popular in the United States until the 1980s, when Japanese manufacturers demonstrated how small and efficient it could be.
It’s faster and makes less exhaust.
It’s cheaper and can use watered-down gas.
What are two other terms for engine knock?
banging and clunking
clicking and clacking
pinging and detonation
Pinging is another way to describe the sound, and detonation describes what’s causing it.
Name one of the causes of engine knock.
the wrong spark plugs
There are several causes of engine knock, and experts say that installing the wrong spark plugs is a common problem.
driving too fast
being low on oil
What is an octane rating?
a way to tell how fast a car can go
a way to tell how much the fuel can be compressed
The octane rating relates to how much the fuel can be compressed before it spontaneously ignites. A rating that’s too low can cause the engine to run poorly.
a way to tell how much the engine will wear out
What are the three functions of engine oil?
lubrication, cooling, cleaning
Most people know that engine oil lubricates to help with metal-on-metal contact, but it also helps cool and clean the engine as it circulates.
lubrication, getting rid of exhaust smell, making gas more powerful
cooling, cleaning, making more money for Jiffy Lube
Why does engine oil need to be changed?
The engine’s movement compresses too much oil.
It gets too dirty to work.
Because engine oil cleans the engine, it picks up dirt and debris as it circulates, which gradually reduces its efficiency.
The oil evaporates in the summer.
What does ECM stand for, and what does it do?
engine control module, which is the engine’s computer
ECM is the engine control module, and it’s the computer that manages the engine’s functions.
engine catheter manager, which controls the oil coming out of the engine
European custom mechanical, which helps race car owners keep track of their modifications
What is an engine’s redline?
how much nitrous oxide you can use
an engine’s maximum rpms
An engine’s redline, which is shown on the tachometer, determines its maximum revolutions per minute, or rpms.
an equation that determines when the turbo kicks in
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