Question 1

Explain the relationship of CO2 emission levels to the air/fuel ratio in the internal combustion engine.

Accepted Answer

CO₂ emission levels are highest at the stoichiometric air/fuel ratio. These emissions decrease if the air/fuel ratio is rich or lean.

Question 2

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 B

Question 3

When the vehicle is running rich, oxygen levels are at their highest point.

Accepted Answer

A) True 
 B)False  False

Question 4

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

Accepted Answer

NO_X levels

Question 5

List the five emission gases today's repair technician can measure with a shop-grade emissions analyzer, and whether each is measured in parts per million (ppm) or as a percentage.

Accepted Answer

NO_X emissions are measured in p

Question 6

For every gallon of gasoline burned, about how much water leaves the tailpipe in vapor form?

Accepted Answer

A)  one pint 
B)  one quart 
C)  three quarts 
D)  one gallon 
A)  one pint 
B)  one quart 
C)  three quarts 
D)  one gallon

Question 7

CO levels are highest when the vehicle is operating at the stoichiometric ratio.

Accepted Answer

A) True 
 B)False

Question 8

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

Accepted Answer

A) True 
 B)False

Question 9

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

Accepted Answer

A) True 
 B)False

Question 10

The CO emission levels are a moderate indicator of what type of air/fuel ratio?

Accepted Answer

Rich runni

Question 11

Oxygen levels are highest when the vehicle is operating at the stoichiometric ratio.

Accepted Answer

A) True 
 B)False

Question 12

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

Accepted Answer

Determine

Question 13

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

Accepted Answer

Any condition that will result

Question 14

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 15

High levels of NOX emissions may be the result of a lean air/fuel mixture.

Accepted Answer

A) True 
 B)False

Question 16

Oxides of nitrogen are always present in the exhaust stream as it leaves the combustion chamber.

Accepted Answer

A) True 
 B)False

Question 17

Why should you operate the exhaust emissions analyzer for 15 minutes after you complete the testing?

Accepted Answer

A)  to dry the moisture from the analyzer 
B)  to provide longer equipment life 
C)  only B 
D)  both A and B 
A)  to dry the moisture from the analyzer 
B)  to provide longer equipment life 
C)  only B 
D)  both A and B

Question 18

How do Tier 2 emissions standards affect the automotive industry?

Accepted Answer

The Tier 2 emission standards set more s

Question 19

Why should you regularly clean the water trap and change the filters of the analyzer?

Accepted Answer

A)  to maintain accurate analyzer readings 
B)  to prevent analyzer damage 
C)  only A 
D)  both A and B 
A)  to maintain accurate analyzer readings 
B)  to prevent analyzer damage 
C)  only A 
D)  both A and B

Question 20

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

Explain the relationship of CO₂ emission levels to the air/fuel ratio in the internal combustion engine.

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?

When the vehicle is running rich, oxygen levels are at their highest point.

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

List the five emission gases today's repair technician can measure with a shop-grade emissions analyzer, and whether each is measured in parts per million (ppm) or as a percentage.

For every gallon of gasoline burned, about how much water leaves the tailpipe in vapor form?

CO levels are highest when the vehicle is operating at the stoichiometric ratio.

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

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

The CO emission levels are a moderate indicator of what type of air/fuel ratio?

Oxygen levels are highest when the vehicle is operating at the stoichiometric ratio.

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

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

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

High levels of NO_X emissions may be the result of a lean air/fuel mixture.

Oxides of nitrogen are always present in the exhaust stream as it leaves the combustion chamber.

Why should you operate the exhaust emissions analyzer for 15 minutes after you complete the testing?

How do Tier 2 emissions standards affect the automotive industry?

Why should you regularly clean the water trap and change the filters of the analyzer?

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?

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 Sensors Output Actuators Diagnosis

Fuel System and Related Input Sensors Output 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: I M Failure Diagnosis and Five Gas Exhaust Analysis

Explain the relationship of CO2 emission levels to the air/fuel ratio in the internal combustion engine.

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?

When the vehicle is running rich, oxygen levels are at their highest point.

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

List the five emission gases today's repair technician can measure with a shop-grade emissions analyzer, and whether each is measured in parts per million (ppm) or as a percentage.

For every gallon of gasoline burned, about how much water leaves the tailpipe in vapor form?

CO levels are highest when the vehicle is operating at the stoichiometric ratio.

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

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

The CO emission levels are a moderate indicator of what type of air/fuel ratio?

Oxygen levels are highest when the vehicle is operating at the stoichiometric ratio.

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

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

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

High levels of NOX emissions may be the result of a lean air/fuel mixture.

Oxides of nitrogen are always present in the exhaust stream as it leaves the combustion chamber.

Why should you operate the exhaust emissions analyzer for 15 minutes after you complete the testing?

How do Tier 2 emissions standards affect the automotive industry?

Why should you regularly clean the water trap and change the filters of the analyzer?

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?

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 Sensors Output Actuators Diagnosis

Fuel System and Related Input Sensors Output Actuators Diagnosis

Emission Control and Evaporative Systems

Strategies of on Board Diagnostic Continuous Monitors

Strategies of on Board Diagnostic Non Continuous Monitors

Filters

Explain the relationship of CO₂ emission levels to the air/fuel ratio in the internal combustion engine.

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

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

High levels of NO_X emissions may be the result of a lean air/fuel mixture.

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?