Question 1

The evaporative emissions system reduces the emissions of HC vapors into the atmosphere when the vehicle:

Accepted Answer

A)  is operating at highway speeds 
B)  is stationary and the engine is idling 
C)  is parked with the engine off 
D)  all of the above 
A)  is operating at highway speeds 
B)  is stationary and the engine is idling 
C)  is parked with the engine off 
D)  all of the above

Question 2

Technician A says that if the fuel tank is full on an OBD II vehicle, the EVAP monitor may not run. Technician B says that if the fuel tank is empty on an OBD II vehicle, the EVAP monitor may not run. Who is correct?

Accepted Answer

A)  A only 
B)  B only 
C)  both A and B 
D)  neither A nor B 
A)  A only 
B)  B only 
C)  both A and B 
D)  neither A nor B

Question 3

A PCV valve stuck in the open position may cause a lean air/fuel ratio.

Accepted Answer

A) True 
 B)False

Question 4

Technician A says the output of the air pump is directed to the area between the reduction and the oxidation catalyst. Technician B says the output of the air pump is directed to the exhaust manifolds just behind the exhaust valves. Who is correct?

Accepted Answer

A)  A only 
B)  B only 
C)  both A and B 
D)  neither A nor B 
A)  A only 
B)  B only 
C)  both A and B 
D)  neither A nor B

Question 5

A restricted canister vent valve could cause an OBD II DTC to be stored for "Evaporative Emission Control System Incorrect Purge Flow."

Accepted Answer

A) True 
 B)False

Question 6

Explain the construction of a modern three-way catalyst and the elements it is made of.

Accepted Answer

Modern catalytic converters utilize a th

Question 7

Why were the dual bed catalytic converters developed?

Accepted Answer

They were developed

Question 8

All of the following statements about the EGR valve are true, EXCEPT:

Accepted Answer

A)  the EGR valve creates a controlled vacuum leak between the intake and exhaust manifolds 
B)  an EGR valve that is stuck closed will cause high NOX emissions 
C)  the vacuum to many vacuum actuated EGR valves is controlled by a solenoid 
D)  an EGR valve that is stuck in the open position will cause detonation 
A)  the EGR valve creates a controlled vacuum leak between the intake and exhaust manifolds 
B)  an EGR valve that is stuck closed will cause high NOX emissions 
C)  the vacuum to many vacuum actuated EGR valves is controlled by a solenoid 
D)  an EGR valve that is stuck in the open position will cause detonation

Question 9

The benefits of emission control systems are to:

Accepted Answer

A)  control hydrocarbon fuel vapors from escaping into the atmosphere 
B)  convert harmful exhaust gases into less harmful emissions before they leave the tailpipe 
C)  reduce fuel consumption 
D)  all of the above 
A)  control hydrocarbon fuel vapors from escaping into the atmosphere 
B)  convert harmful exhaust gases into less harmful emissions before they leave the tailpipe 
C)  reduce fuel consumption 
D)  all of the above

Question 10

If the catalytic converter is working properly, the outlet temperature should be lower than the inlet temperature.

Accepted Answer

A) True 
 B)False

Question 11

The EGR system is designed to reduce which emission gas?

Accepted Answer

Oxides of

Question 12

Which of the following is the best definition for the catalytic converter?

Accepted Answer

A)  a device that produces maximum combustion inside the engine 
B)  a way of cleaning up the exhaust gases after they leave the engine 
C)  a device that creates extra oxygen to overcome exhaust gases 
D)  a method of emission control that is now being discontinued 
A)  a device that produces maximum combustion inside the engine 
B)  a way of cleaning up the exhaust gases after they leave the engine 
C)  a device that creates extra oxygen to overcome exhaust gases 
D)  a method of emission control that is now being discontinued

Question 13

Describe the operation of the PCV valve as it relates to engine speed.

Accepted Answer

The PCV valve is moved toward the open p

Question 14

What does the three-way catalyst do, and what is the conversion efficiency of the catalyst?

Accepted Answer

The three-way catalyst causes a chemical

Question 15

A defective EGR system will cause NOX emissions to be higher than normal.

Accepted Answer

A) True 
 B)False

Question 16

If the fuel filler cap leaks, what monitor is designed to detect the leak?

Accepted Answer

A)  the catalyst efficiency monitor 
B)  the misfire monitor 
C)  the EVAP system monitor 
D)  none of the above 
A)  the catalyst efficiency monitor 
B)  the misfire monitor 
C)  the EVAP system monitor 
D)  none of the above

Question 17

An aftermarket air intake system could affect emission levels.

Accepted Answer

A) True 
 B)False

Question 18

Technician A says that the PCV is an emission control device. Technician B says that current vehicles monitor the operation of the PCV system. Who is correct?

Accepted Answer

A)  A only 
B)  B only 
C)  both A and B 
D)  neither A nor B 
A)  A only 
B)  B only 
C)  both A and B 
D)  neither A nor B

Question 19

The benefits of emission controls are to:

Accepted Answer

A)  reduce pollutants in the exhaust stream 
B)  control vapor loss into the atmosphere 
C)  reduce fuel consumption 
D)  all of the above 
A)  reduce pollutants in the exhaust stream 
B)  control vapor loss into the atmosphere 
C)  reduce fuel consumption 
D)  all of the above

Question 20

Before performing an emission system diagnosis, the emission control system should be inspected for modification, tampering, and/or missing parts.

Accepted Answer

A) True 
 B)False

The evaporative emissions system reduces the emissions of HC vapors into the atmosphere when the vehicle:

Technician A says that if the fuel tank is full on an OBD II vehicle, the EVAP monitor may not run. Technician B says that if the fuel tank is empty on an OBD II vehicle, the EVAP monitor may not run. Who is correct?

A PCV valve stuck in the open position may cause a lean air/fuel ratio.

Technician A says the output of the air pump is directed to the area between the reduction and the oxidation catalyst. Technician B says the output of the air pump is directed to the exhaust manifolds just behind the exhaust valves. Who is correct?

A restricted canister vent valve could cause an OBD II DTC to be stored for "Evaporative Emission Control System Incorrect Purge Flow."

Explain the construction of a modern three-way catalyst and the elements it is made of.

Why were the dual bed catalytic converters developed?

All of the following statements about the EGR valve are true, EXCEPT:

The benefits of emission control systems are to:

If the catalytic converter is working properly, the outlet temperature should be lower than the inlet temperature.

The EGR system is designed to reduce which emission gas?

Which of the following is the best definition for the catalytic converter?

Describe the operation of the PCV valve as it relates to engine speed.

What does the three-way catalyst do, and what is the conversion efficiency of the catalyst?

A defective EGR system will cause NO_X emissions to be higher than normal.

If the fuel filler cap leaks, what monitor is designed to detect the leak?

An aftermarket air intake system could affect emission levels.

Technician A says that the PCV is an emission control device. Technician B says that current vehicles monitor the operation of the PCV system. Who is correct?

The benefits of emission controls are to:

Before performing an emission system diagnosis, the emission control system should be inspected for modification, tampering, and/or missing parts.

Emissions and Engine Performance Overview

Basic Theories

History of On-Board Diagnostics Obd

On-Board Diagnostic Scanners and Digital Storage Oscilloscopes

Computers and Input Sensors

Ignition System and Related Input Sensorsoutput Actuators Diagnosis

Fuel System and Related Input Sensorsoutput Actuators Diagnosis

Strategies of On-Board Diagnostic Continuous Monitors

Strategies of On-Board Diagnostic Non-Continuous Monitors

Im Failure Diagnosis and Five-Gas Exhaust Analysis

Filters

Exam 8: Emission Control and Evaporative Systems

The evaporative emissions system reduces the emissions of HC vapors into the atmosphere when the vehicle:

Technician A says that if the fuel tank is full on an OBD II vehicle, the EVAP monitor may not run. Technician B says that if the fuel tank is empty on an OBD II vehicle, the EVAP monitor may not run. Who is correct?

A PCV valve stuck in the open position may cause a lean air/fuel ratio.

Technician A says the output of the air pump is directed to the area between the reduction and the oxidation catalyst. Technician B says the output of the air pump is directed to the exhaust manifolds just behind the exhaust valves. Who is correct?

A restricted canister vent valve could cause an OBD II DTC to be stored for "Evaporative Emission Control System Incorrect Purge Flow."

Explain the construction of a modern three-way catalyst and the elements it is made of.

Why were the dual bed catalytic converters developed?

All of the following statements about the EGR valve are true, EXCEPT:

The benefits of emission control systems are to:

If the catalytic converter is working properly, the outlet temperature should be lower than the inlet temperature.

The EGR system is designed to reduce which emission gas?

Which of the following is the best definition for the catalytic converter?

Describe the operation of the PCV valve as it relates to engine speed.

What does the three-way catalyst do, and what is the conversion efficiency of the catalyst?

A defective EGR system will cause NOX emissions to be higher than normal.

If the fuel filler cap leaks, what monitor is designed to detect the leak?

An aftermarket air intake system could affect emission levels.

Technician A says that the PCV is an emission control device. Technician B says that current vehicles monitor the operation of the PCV system. Who is correct?

The benefits of emission controls are to:

Before performing an emission system diagnosis, the emission control system should be inspected for modification, tampering, and/or missing parts.

Emissions and Engine Performance Overview

Basic Theories

History of On-Board Diagnostics Obd

On-Board Diagnostic Scanners and Digital Storage Oscilloscopes

Computers and Input Sensors

Ignition System and Related Input Sensorsoutput Actuators Diagnosis

Fuel System and Related Input Sensorsoutput Actuators Diagnosis

Strategies of On-Board Diagnostic Continuous Monitors

Strategies of On-Board Diagnostic Non-Continuous Monitors

Im Failure Diagnosis and Five-Gas Exhaust Analysis

Filters

A defective EGR system will cause NO_X emissions to be higher than normal.