Question 1

If a vehicle is repaired that failed a state emissions test for CO, what pollutant could potentially increase after the repair?

Accepted Answer

A)  HC 
B)  NOX 
C)  CO 
D)  O2 
A)  HC 
B)  NOX 
C)  CO 
D)  O2 B

Question 2

If the emission levels on a 4-gas analyzer indicate that CO2 is high and HC, O2 and CO are all low, what could this indicate?

Accepted Answer

A)  a rich mixture 
B)  a lean mixture 
C)  the stoichiometric mixture 
D)  none of the above 
A)  a rich mixture 
B)  a lean mixture 
C)  the stoichiometric mixture 
D)  none of the above C

Question 3

What are hydrocarbon emissions the result of?

Accepted Answer

Hydrocarbons are the result of any condition that causes incomplete combustion.

Question 4

If the emission levels on a 4-gas analyzer indicate that both O2 and HC are high and CO2 and CO are both low, what could this indicate?

Accepted Answer

A)  a rich mixture 
B)  a lean mixture 
C)  the stoichiometric mixture 
D)  none of the above 
A)  a rich mixture 
B)  a lean mixture 
C)  the stoichiometric mixture 
D)  none of the above

Question 5

What are the only byproducts left after ideal combustion in the internal combustion gasoline engine?

Accepted Answer

Water, carbon dioxid

Question 6

If the EGR intake passages are partially blocked but the EGR valve mechanically and electrically functions correctly, how and when would emissions be affected?

Accepted Answer

NO_X levels will incre

Question 7

List the five emission gases today's repair technician can measure with a shop-grade emissions analyzer, and what volume is each measured in?

Accepted Answer

NO_X emissions are measured in p

Question 8

As the air/fuel ratio becomes leaner, the higher the NOX emissions will be until what point?

Accepted Answer

The point of extreme

Question 9

How and when are nitrogen oxide (NOX) emissions formed in the internal combustion engine?

Accepted Answer

Nitrogen oxides (NO_X) are formed in the c

Question 10

The level oxides of nitrogen exhaust emissions are highest when the air/fuel ratio is slightly rich.

Accepted Answer

A) True 
 B)False

Question 11

The levels of carbon dioxide exhaust emissions are highest when the air/fuel ratio is lean.

Accepted Answer

A) True 
 B)False

Question 12

If the emission levels on a 4-gas analyzer indicate that both CO and HC are high and both O2 and CO2 are low, what could this indicate?

Accepted Answer

A)  a rich mixture 
B)  a lean mixture 
C)  the stoichiometric mixture 
D)  none of the above 
A)  a rich mixture 
B)  a lean mixture 
C)  the stoichiometric mixture 
D)  none of the above

Question 13

A vehicle that has failed a state emissions inspection for high CO levels may have a problem with a:

Accepted Answer

A)  fuel-saturated EVAP canister 
B)  defective EGR valve 
C)  defective fuel filler cap 
D)  none of the above 
A)  fuel-saturated EVAP canister 
B)  defective EGR valve 
C)  defective fuel filler cap 
D)  none of the above

Question 14

Water may be present in the combustion chamber during the combustion process as a result of:

Accepted Answer

A)  a normal byproduct of combustion 
B)  contaminated fuel 
C)  atmospheric humidity 
D)  all of the above 
A)  a normal byproduct of combustion 
B)  contaminated fuel 
C)  atmospheric humidity 
D)  all of the above

Question 15

Describe how HC emissions are formed, and explain the relationship of these emissions to the air/fuel ratio.

Accepted Answer

HC emissions are formed by unburned fuel

Question 16

What is carbon monoxide the result of in the internal combustion engine?

Accepted Answer

Carbon monoxide (CO) is one of

Question 17

The three main pollutants caused by a motor vehicle are carbon monoxide, hydrocarbons, and oxides of nitrogen.

Accepted Answer

A) True 
 B)False

Question 18

What condition in the internal combustion engine will result in elevated nitrogen oxide (NOX) levels?

Accepted Answer

Any condition that will result

Question 19

Oxygenated fuel is designed to reduce which of the following pollutants?

Accepted Answer

A)  CO 
B)  HC 
C)  NOX 
D)  all of the above 
A)  CO 
B)  HC 
C)  NOX 
D)  all of the above

Question 20

What should you do before beginning any diagnostic and repair procedure using an emissions analyzer, before performing any repairs?

Accepted Answer

Base-line

If a vehicle is repaired that failed a state emissions test for CO, what pollutant could potentially increase after the repair?

If the emission levels on a 4-gas analyzer indicate that CO₂ is high and HC, O₂ and CO are all low, what could this indicate?

What are hydrocarbon emissions the result of?

If the emission levels on a 4-gas analyzer indicate that both O₂ and HC are high and CO₂ and CO are both low, what could this indicate?

What are the only byproducts left after ideal combustion in the internal combustion gasoline engine?

If the EGR intake passages are partially blocked but the EGR valve mechanically and electrically functions correctly, how and when would emissions be affected?

List the five emission gases today's repair technician can measure with a shop-grade emissions analyzer, and what volume is each measured in?

As the air/fuel ratio becomes leaner, the higher the NO_X emissions will be until what point?

How and when are nitrogen oxide (NO_X) emissions formed in the internal combustion engine?

The level oxides of nitrogen exhaust emissions are highest when the air/fuel ratio is slightly rich.

The levels of carbon dioxide exhaust emissions are highest when the air/fuel ratio is lean.

If the emission levels on a 4-gas analyzer indicate that both CO and HC are high and both O₂ and CO₂ are low, what could this indicate?

A vehicle that has failed a state emissions inspection for high CO levels may have a problem with a:

Water may be present in the combustion chamber during the combustion process as a result of:

Describe how HC emissions are formed, and explain the relationship of these emissions to the air/fuel ratio.

What is carbon monoxide the result of in the internal combustion engine?

The three main pollutants caused by a motor vehicle are carbon monoxide, hydrocarbons, and oxides of nitrogen.

What condition in the internal combustion engine will result in elevated nitrogen oxide (NO_X) levels?

Oxygenated fuel is designed to reduce which of the following pollutants?

What should you do before beginning any diagnostic and repair procedure using an emissions analyzer, before performing any repairs?

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

Emission Control and Evaporative Systems

Strategies of On-Board Diagnostic Continuous Monitors

Strategies of On-Board Diagnostic Non-Continuous Monitors

Filters

Exam 11: Im Failure Diagnosis and Five-Gas Exhaust Analysis

If a vehicle is repaired that failed a state emissions test for CO, what pollutant could potentially increase after the repair?

If the emission levels on a 4-gas analyzer indicate that CO2 is high and HC, O2 and CO are all low, what could this indicate?

What are hydrocarbon emissions the result of?

If the emission levels on a 4-gas analyzer indicate that both O2 and HC are high and CO2 and CO are both low, what could this indicate?

What are the only byproducts left after ideal combustion in the internal combustion gasoline engine?

If the EGR intake passages are partially blocked but the EGR valve mechanically and electrically functions correctly, how and when would emissions be affected?

List the five emission gases today's repair technician can measure with a shop-grade emissions analyzer, and what volume is each measured in?

As the air/fuel ratio becomes leaner, the higher the NOX emissions will be until what point?

How and when are nitrogen oxide (NOX) emissions formed in the internal combustion engine?

The level oxides of nitrogen exhaust emissions are highest when the air/fuel ratio is slightly rich.

The levels of carbon dioxide exhaust emissions are highest when the air/fuel ratio is lean.

If the emission levels on a 4-gas analyzer indicate that both CO and HC are high and both O2 and CO2 are low, what could this indicate?

A vehicle that has failed a state emissions inspection for high CO levels may have a problem with a:

Water may be present in the combustion chamber during the combustion process as a result of:

Describe how HC emissions are formed, and explain the relationship of these emissions to the air/fuel ratio.

What is carbon monoxide the result of in the internal combustion engine?

The three main pollutants caused by a motor vehicle are carbon monoxide, hydrocarbons, and oxides of nitrogen.

What condition in the internal combustion engine will result in elevated nitrogen oxide (NOX) levels?

Oxygenated fuel is designed to reduce which of the following pollutants?

What should you do before beginning any diagnostic and repair procedure using an emissions analyzer, before performing any repairs?

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

Emission Control and Evaporative Systems

Strategies of On-Board Diagnostic Continuous Monitors

Strategies of On-Board Diagnostic Non-Continuous Monitors

Filters

If the emission levels on a 4-gas analyzer indicate that CO₂ is high and HC, O₂ and CO are all low, what could this indicate?

If the emission levels on a 4-gas analyzer indicate that both O₂ and HC are high and CO₂ and CO are both low, what could this indicate?

As the air/fuel ratio becomes leaner, the higher the NO_X emissions will be until what point?

How and when are nitrogen oxide (NO_X) emissions formed in the internal combustion engine?

If the emission levels on a 4-gas analyzer indicate that both CO and HC are high and both O₂ and CO₂ are low, what could this indicate?

What condition in the internal combustion engine will result in elevated nitrogen oxide (NO_X) levels?