Deck 11: I M Failure Diagnosis and Five Gas Exhaust Analysis

Question 1

An emissions grade dynamometer allows a repair facility to simulate vehicle:

A) acceleration
B) steady state cruise
C) deceleration
D) all of the above

Answer 1

D

Question 2

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

Answer 2

False

Question 3

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

Answer 3

False

Question 4

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

Question 5

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

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

Question 6

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

Question 7

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

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

Question 8

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

Question 9

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

A) HC
B) NO_X
C) CO
D) O₂

Question 10

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

Question 11

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?

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

Question 12

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

Question 13

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

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

Question 14

A faulty spark plug wire will cause HC emissions to increase.

Question 15

Under extreme temperatures and pressures, nitrogen is forced to combine with oxygen in the combustion chamber to form oxides of nitrogen.

Question 16

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

Question 17

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?

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

Question 18

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

Question 19

What is the reason for wearing protective gloves when you handle the analyzer probe and sample hose after the vehicle has been running?

A) The parts are sharp.
B) The parts can be damaged by sweat.
C) The parts are very hot.
D) The parts contain acids.

Question 20

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

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

Question 21

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

Question 22

What should you do to the secondary air injection system while diagnosing the cause of an emissions failure or performance problem?

Question 23

How can you use the exhaust gas analyzer to determine the effectiveness of your repair?

Question 24

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

Question 25

Write the three parts of the general chemical formula for the dilution correction factor.

Question 26

Describe CO emissions in relation to the air/fuel ratio, and explain how these emissions are formed.

Question 27

What gases is the five-gas emissions analyzer capable of monitoring?

Question 28

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

Question 29

Write the chemical formula for the actual combustion gas chemistry equation for the internal combustion engine.

Question 30

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

Question 31

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

Question 32

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

Question 33

How can oxygen levels be used to indicate a rich air/fuel ratio?

Question 34

What are hydrocarbon emissions the result of?

Question 35

How do Tier 2 emissions standards affect the automotive industry?

Question 36

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

Question 37

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

Question 38

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.

Question 39

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

Question 40

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