Question 1

Two technicians are discussing bearing inspection. Technician A says that you can reuse a race if only the bearing is damaged. Technician B says that bearings come pre-lubricated from the factory. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

D

Question 2

The charging system consists of the generator, battery, and starter.

Accepted Answer

The charging system consists of the generator (alternatively called the alternator), battery, and voltage regulator. The starter is part of the starting system, not the charging system.

Question 3

The amount of air that an engine can move in one cycle is its displacement.

Accepted Answer

Displacement refers to the total volume of air and fuel that an engine can move in one complete cycle of all its cylinders.

Question 4

Today's engine design is very different from the original basic engine design from the 1890's.

Accepted Answer

Over the years, engine designs have improved greatly with the incorporation of advanced technologies and innovations. The basic design principles have remained the same but the execution and efficiency have been improved drastically.

Question 5

Four-cylinder, in-line, gasoline engines are used less frequently in modern cars because of the block's weight and size.

Accepted Answer

Four-cylinder, in-line, gasoline engines are actually quite common in modern cars as they tend to be more fuel efficient and have lower emissions compared to larger engines.

Question 6

Two technicians are discussing PCV systems. Technician A says that PCV systems are connected to a port on the intake manifold. Technician B says that PCV systems prevent the fuel tank from over-pressurizing. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

Technician A is correct that PCV systems are connected to a port on the intake manifold to regulate the flow of crankcase fumes back into the engine for combustion. Technician B is incorrect as PCV systems have no connection to the fuel tank and do not prevent over-pressurization.

Question 7

What is true of installing bearing grease?
A) Do not fill the hub completely with grease.
B) Grease can melt if installed improperly.
C) Grease must be the correct type for the application.
D) All solvent must be dried before installing new grease.

Accepted Answer

The answer of What is true of installing bearing grease?
A)...

Question 8

All rollers or balls of a bearing must be lubricated for a bearing to be properly lubricated

Accepted Answer

All the rolling elements, whether they are rollers or balls, must be lubricated for a bearing to function properly. Without proper lubrication, the rolling elements may experience excessive friction and wear, leading to premature failure of the bearing.

Question 9

A rotary engine uses a rotor to compress the air/fuel mixture.

Accepted Answer

A rotary engine uses a rotor, which is triangular or elliptical in shape, to compress the air/fuel mixture. The movement of the rotor creates different spaces inside the engine that trap and compress the air/fuel mixture, leading to combustion and power production.

Question 10

Two technicians are discussing engine operation. Technician A says that valve timing is critical to smooth engine operation. Technician B says that ignition timing is critical to smooth engine operation. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

Both valve timing and ignition timing are critical to smooth engine operation. Valve timing determines the flow of air and fuel into and out of the engine, while ignition timing determines when the spark plug fires and ignites the air/fuel mixture. Both need to be finely tuned for optimal engine performance.

Question 11

Two technicians are discussing EFI systems. Technician A says that most modern EFI systems have one injector per cylinder. Technician B says that direct injection uses one central injector for the engine. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

Most modern EFI systems do have one injector per cylinder. Technician B is incorrect as direct injection does not use one central injector for the engine, but instead has an injector for each cylinder or a central injector for each bank of cylinders.

Question 12

Pressurized oil is required to maintain a space between the rod bearing and the crankshaft.

Accepted Answer

Pressurized oil is necessary to form a film of oil between the rod bearing and the crankshaft in order to reduce friction and prevent metal-to-metal contact. Without this oil pressure, the bearing and crankshaft would quickly wear and potentially seize up.

Question 13

The powertrain has become the most complex system in the vehicle.

Accepted Answer

With the introduction of hybrid and electric technologies, as well as various transmission options and advanced engine management systems, the powertrain has become increasingly complex.

Question 14

Older vehicles use a(n) _____ catalytic converter.
A) one-way
B) two-way
C) three-way
D) four-way

Accepted Answer

Older vehicles typically use a two-way catalytic converter. This type of converter can only convert carbon monoxide (CO) and hydrocarbons (HC) into carbon dioxide (CO2) and water (H2O). It does not have the ability to reduce nitrogen oxides (NOx). More modern vehicles use three-way or four-way converters, which have additional components to reduce NOx emissions.

Question 15

Most bearing failures result directly from improper installation.

Accepted Answer

The answer of Most bearing failures result directly from improper...

Question 16

What is a characteristic of a rotary engine?
A) Turns in two directions with the stop-and-start motion of a piston
B) Has the same problem with harmful emissions as piston engines
C) Produces less horsepower with more wasted energy than a conventional reciprocating engine
D) Is more efficient producing more torque than a piston engine of the same displacement

Accepted Answer

Rotary engines, like piston engines, can have issues with harmful emissions due to incomplete combustion and the shape of the combustion chamber.

Question 17

Two technicians are discussing automotive power systems. Technician A says that today's engines operate on different principles than those of the past. Technician B says that today's engine has more computerized sensors and actuators than did an entire vehicle had in the mid-1980's. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

Today's engines have more computerized sensors and actuators compared to entire vehicles from the mid-1980s, but they still operate on the same basic principles of internal combustion.

Question 18

RTV must be matched to the application for which it is being used for.

Accepted Answer

RTV (Room Temperature Vulcanizing) silicone is designed for different applications and should be chosen based on the intended use. Choosing the wrong type of RTV for an application can result in failure or reduced performance.

Question 19

Two technicians are discussing engine sensors. Technician A says that MAP sensors measure altitude. Technician B says MAF sensors measure exhaust flow. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

Both statements are incorrect. MAP (Manifold Absolute Pressure) sensors measure the pressure of the air entering the engine and MAF (Mass Airflow) sensors measure the mass of the air entering the engine. Neither sensor measures altitude or exhaust flow.

Question 20

Two technicians are discussing exhaust systems. Technician A says that exhaust systems were originally designed to clean the exhaust gases. Technician B says that today's cleaner-running vehicles do not need emission devices. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B

Accepted Answer

Exhaust systems were originally designed to quiet the engine noise, not to clean exhaust gases. Modern vehicles still require emission devices to meet environmental standards, despite running cleaner than older models.

Quiz 7: Engine Systems Operation

Two technicians are discussing bearing inspection. Technician A says that you can reuse a race if only the bearing is damaged. Technician B says that bearings come pre-lubricated from the factory. Who is correct?

The charging system consists of the generator, battery, and starter.

The amount of air that an engine can move in one cycle is its displacement.

Today's engine design is very different from the original basic engine design from the 1890's.

Four-cylinder, in-line, gasoline engines are used less frequently in modern cars because of the block's weight and size.

Two technicians are discussing PCV systems. Technician A says that PCV systems are connected to a port on the intake manifold. Technician B says that PCV systems prevent the fuel tank from over-pressurizing. Who is correct?

What is true of installing bearing grease?

All rollers or balls of a bearing must be lubricated for a bearing to be properly lubricated

A rotary engine uses a rotor to compress the air/fuel mixture.

Two technicians are discussing engine operation. Technician A says that valve timing is critical to smooth engine operation. Technician B says that ignition timing is critical to smooth engine operation. Who is correct?

Two technicians are discussing EFI systems. Technician A says that most modern EFI systems have one injector per cylinder. Technician B says that direct injection uses one central injector for the engine. Who is correct?

Pressurized oil is required to maintain a space between the rod bearing and the crankshaft.

The powertrain has become the most complex system in the vehicle.

Older vehicles use a(n) _____ catalytic converter.

Most bearing failures result directly from improper installation.

What is a characteristic of a rotary engine?

Two technicians are discussing automotive power systems. Technician A says that today's engines operate on different principles than those of the past. Technician B says that today's engine has more computerized sensors and actuators than did an entire vehicle had in the mid-1980's. Who is correct?

RTV must be matched to the application for which it is being used for.

Two technicians are discussing engine sensors. Technician A says that MAP sensors measure altitude. Technician B says MAF sensors measure exhaust flow. Who is correct?

Two technicians are discussing exhaust systems. Technician A says that exhaust systems were originally designed to clean the exhaust gases. Technician B says that today's cleaner-running vehicles do not need emission devices. Who is correct?