Deck 24: Intake and Exhaust Systems

Question 1

Intake charge velocity has to be ________ to prevent fuel droplet separation.

A)100 feet per second
B)25 feet per second
C)300 feet per second
D)50 feet per second

Answer 1

50 feet per second

Question 2

The air filter restriction indicator uses what to detect when it signals to replace the filter?

A)The amount of light that can pass through the filter
B)The amount of restriction measured in inches of water
C)Number of miles or vehicle travel
D)Number of hours of engine operation

Answer 2

The amount of restriction measured in inches of water

Question 3

Why are the EGR gases cooled before entering the engine on some engines?

A)To prevent damage to the intake valves
B)To help prevent the exhaust from slowing down
C)To prevent heating the air-fuel mixture in the cylinder
D)Cool exhaust gas is more effective at controlling NOx emissions

Answer 3

Cool exhaust gas is more effective at controlling NOx emissions

Question 4

The air/fuel mixture flows through the intake manifold on what type of system?

A)Port fuel injection
B)Throttle body fuel injection
C)Any fuel injected engine
D)Both port injection and throttle body injection

Question 5

Air filters can remove particles and dirt as small as ________.

A)5 to 10 microns
B)40 to 50 microns
C)30 to 40 microns
D)10 to 25 microns

Question 6

Why do many port fuel injected engines use long intake runners?

A)To increase low RPM torque
B)To increase high RPM power
C)To reduce exhaust emissions
D)To heat the incoming air

Question 7

Exhaust passages are included in some intake manifolds. Technician A says that the exhaust passages are used for exhaust gas recirculation (EGR) systems. Technician B says that the upper intake is often called the plenum. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 8

The upper portion of a two part intake manifold is often called the ________.

A)Housing
B)Plenum
C)Lower part
D)Vacuum chamber

Question 9

Technician A says that a cracked exhaust manifold can affect engine operation. Technician B says that a leaking lower intake manifold gasket could cause a vacuum leak. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 10

Technician A says that some intake manifolds are plastic. Technician B says that some intake manifolds are constructed in two parts or sections: upper and lower. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 11

All of these are main jobs of the air cleaner and filter parts, EXCEPT ________.

A)Silence the intake air noise
B)Act as a flame arrester in case of a backfire
C)Lower the intake air temperature
D)Clean the air before it is mixed with fuel

Question 12

Technician A says that exhaust manifolds can be made from hard plastic or aluminum. Technician B says that many intake manifolds have an EGR valve that regulates the amount of recirculated exhaust that enters the engine in order to increase NO_x emissions. Who is right?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 13

Technician A says that the exhaust system also contains a catalytic converter, exhaust pipes, and muffler. Technician B says that the entire exhaust system is supported by metal hangers that isolate the noise and vibration of the exhaust from the rest of the vehicle. Who is right?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 14

The intake manifold of a port fuel-injected engine does which of these?

A)Uses a leaner air-fuel mixture than TBI
B)Contains only air
C)Contains only fuel
D)Uses a heater to heat the intake air

Question 15

Technician A says that intake manifolds are always made of metal. Technician B says that some intake manifolds are constructed in two parts or sections, upper and lower. Who is right?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 16

The automotive engine uses about ________ gallons of air for every gallon of gasoline burned at an air-fuel ratio of 14.7 to 1.

A)9000
B)7000
C)2000
D)4000

Question 17

Some systems also have a(n) ________ sensor between the throttle body and the air cleaner.

A)Mass airflow (MAF)
B)Exhaust gas sensor (EGS)
C)Air temperature
D)Throttle position sensor (TPS)

Question 18

Manifold sizes represent a compromise. They must have a cross-section large enough to allow charge flow for a maximum amount of ________.

A)Speed
B)Torque
C)Flow resistance
D)Power

Question 19

Shorter runners in a port fuel injected engine provide which of these?

A)Minimum high-RPM power
B)Minimum low-RPM power
C)Increased high-RPM power
D)Increased low-RPM power

Question 20

A cracked exhaust manifold can cause false readings from which of these engine sensors?

A)Oxygen sensor
B)Exhaust temperature sensor
C)Coolant temperature sensor
D)Intake air temperature sensor