Question 1

The OBD-II evaporative emission system monitor on a 2008 vehicle can detect a hole as small as ________.

Accepted Answer

A)   0.200" diameter
B)   0.020" diameter
C)   0.400" diameter
D)   0.040" diameterE) B) and C)
F) A) and C)

Question 2

Which exhaust emission is formed by high combustion chamber temperatures?

Accepted Answer

A)   HC
B)   NOx 
C)   CO2 
D)   COE) B) and D)
F) B) and C)

Question 3

A vacuum gauge is being used to check for a restricted exhaust system. The vacuum at idle is 18 in. Hg. Which of these results indicates a restriction?

Accepted Answer

A)   Vacuum at 2,500 RPM is 22 in. Hg.
B)   Vacuum at 2,500 RPM is 19 in. Hg.
C)   Vacuum at 2,500 RPM is 9 in. Hg.
D)   Not enough information to diagnoseE) C) and D)
F) B) and D)

Question 4

Which device protects the air pump from reverse exhaust pressure?

Accepted Answer

A)   IAC valve
B)   Check valve
C)   EGR valve
D)   PCV valveE) A) and B)
F) A) and D)

Question 5

All of the following statements are correct EXCEPT ________.

Accepted Answer

A)   linear EGR systems require exhaust backpressure
B)   many vehicles use the MAP sensor to monitor EGR operation
C)   some systems use a delta pressure feedback system to monitor EGR operation by measuring exhaust system pressure
D)   OBD-II vehicles require monitoring of the EGR systemE) B) and D)
F) B) and C)

Question 6

Technician A says that PCV valves should rattle when shaken. Technician B says that defective PCV systems may cause leaking engine seals. Which technician is correct?

Accepted Answer

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

Question 7

All these are causes of catalytic converter failure EXCEPT ________.

Accepted Answer

A)   contamination
B)   excessive water vapor
C)   incorrect air/fuel mixture
D)   excessive temperatureE) B) and D)
F) A) and D)

Question 8

All of these are components of smog EXCEPT ________.

Accepted Answer

A)   AIR
B)   NOx 
C)   Fog
D)   HCE) A) and B)
F) A) and C)

Question 9

Which component sends fresh air to the catalytic converter to help oxidize emissions?

Accepted Answer

A)   AIR pump
B)   PCV valve
C)   Thermostatic air cleaner
D)   EGR valveE) All of the above
F) A) and D)

Question 10

Technician A says that a 3 x 5 card should be held against the oil fill opening if the PCV system is operating correctly. Technician B says that if a PCV valve rattles, it definitely is good. Which technician is correct?

Accepted Answer

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

Question 11

Technician A says that CO and HC levels should increase if the AIR hoses are pinched off. Technician B says that a defective drive belt may cause AIR system problems. Which technician is correct?

Accepted Answer

A)   Technician A only
B)   Technician B only
C)   Both technicians A and B
D)   Neither technician A nor BE) C) and D)
F) None of the above

Question 12

Where is air from the AIR pump directed when the engine is cold?

Accepted Answer

A)   Air cleaner
B)   Atmosphere
C)   Catalytic converter
D)   Exhaust manifoldE) A) and B)
F) B) and D)

Question 13

A state inspection of the EVAP system includes ________.

Accepted Answer

A)   checking the level of fuel in the tank
B)   pressurizing the EVAP system
C)   testing the gas cap for proper sealing
D)   Both A and BE) B) and C)
F) A) and B)

Question 14

Technician A says that some crankcase vent systems use a calibrated orifice instead of a PCV valve. Technician B says that turbocharged engines often use an oil/water separator in the PCV system. Which technician is correct?

Accepted Answer

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

Question 15

What term is used to describe combustion gasses leaking past cylinder rings?

Accepted Answer

A)   Manifold pressure
B)   Crankcase build-up
C)   Sludge
D)   Blow byE) All of the above
F) A) and C)

Question 16

The following statements are all correct EXCEPT ________.

Accepted Answer

A)   some systems monitor EGR operation by using a pressure feedback EGR sensor
B)   a potentiometer is used to determine EGR valve position on many OBD-II systems
C)   low restriction exhaust systems will have no effect on EGR system operation
D)   the PCM controls vacuum applied to vacuum operated EGR valvesE) All of the above
F) A) and D)

Exam 27: Emission Control Devices Operation and Diagnosis

Technician A says that PCV valves should rattle when shaken. Technician B says that defective PCV systems may cause leaking engine seals. Which technician is correct?

Correct Answer
verified

Which device protects the air pump from reverse exhaust pressure?

Correct Answer
verified

Which component sends fresh air to the catalytic converter to help oxidize emissions?

Correct Answer
verified

All of the following statements are correct EXCEPT ________.

Correct Answer
verified

The following statements are all correct EXCEPT ________.

Correct Answer
verified

Technician A says that CO and HC levels should increase if the AIR hoses are pinched off. Technician B says that a defective drive belt may cause AIR system problems. Which technician is correct?

Correct Answer
verified

A state inspection of the EVAP system includes ________.

Correct Answer
verified

Technician A says that some crankcase vent systems use a calibrated orifice instead of a PCV valve. Technician B says that turbocharged engines often use an oil/water separator in the PCV system. Which technician is correct?

Correct Answer
verified

All of these are components of smog EXCEPT ________.

Correct Answer
verified

All these are causes of catalytic converter failure EXCEPT ________.

Correct Answer
verified

Which exhaust emission is formed by high combustion chamber temperatures?

Correct Answer
verified

The OBD-II evaporative emission system monitor on a 2008 vehicle can detect a hole as small as ________.

Correct Answer
verified

A vacuum gauge is being used to check for a restricted exhaust system. The vacuum at idle is 18 in. Hg. Which of these results indicates a restriction?

Correct Answer
verified

Technician A says that a 3 x 5 card should be held against the oil fill opening if the PCV system is operating correctly. Technician B says that if a PCV valve rattles, it definitely is good. Which technician is correct?

Correct Answer
verified

Where is air from the AIR pump directed when the engine is cold?

Correct Answer
verified

What term is used to describe combustion gasses leaking past cylinder rings?

Correct Answer
verified

Exam 27: Emission Control Devices Operation and Diagnosis

Technician A says that PCV valves should rattle when shaken. Technician B says that defective PCV systems may cause leaking engine seals. Which technician is correct?

Correct AnswerverifiedShow Answer

Which device protects the air pump from reverse exhaust pressure?

Correct AnswerverifiedShow Answer

Which component sends fresh air to the catalytic converter to help oxidize emissions?

Correct AnswerverifiedShow Answer

All of the following statements are correct EXCEPT ________.

Correct AnswerverifiedShow Answer

The following statements are all correct EXCEPT ________.

Correct AnswerverifiedShow Answer

Technician A says that CO and HC levels should increase if the AIR hoses are pinched off. Technician B says that a defective drive belt may cause AIR system problems. Which technician is correct?

Correct AnswerverifiedShow Answer

A state inspection of the EVAP system includes ________.

Correct AnswerverifiedShow Answer

Technician A says that some crankcase vent systems use a calibrated orifice instead of a PCV valve. Technician B says that turbocharged engines often use an oil/water separator in the PCV system. Which technician is correct?

Correct AnswerverifiedShow Answer

All of these are components of smog EXCEPT ________.

Correct AnswerverifiedShow Answer

All these are causes of catalytic converter failure EXCEPT ________.

Correct AnswerverifiedShow Answer

Which exhaust emission is formed by high combustion chamber temperatures?

Correct AnswerverifiedShow Answer

The OBD-II evaporative emission system monitor on a 2008 vehicle can detect a hole as small as ________.

Correct AnswerverifiedShow Answer

A vacuum gauge is being used to check for a restricted exhaust system. The vacuum at idle is 18 in. Hg. Which of these results indicates a restriction?

Correct AnswerverifiedShow Answer

Technician A says that a 3 x 5 card should be held against the oil fill opening if the PCV system is operating correctly. Technician B says that if a PCV valve rattles, it definitely is good. Which technician is correct?

Correct AnswerverifiedShow Answer

Where is air from the AIR pump directed when the engine is cold?

Correct AnswerverifiedShow Answer

What term is used to describe combustion gasses leaking past cylinder rings?

Correct AnswerverifiedShow Answer

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