Emissions Control Systems

Question 1

Which tailpipe emission would increase during a cylinder misfire?

Answer 1

Hydrocarbon & Oxygen

Question 2

What causes high Hydrocarbon in the emission system?

Answer 2

unburnt fuel
engine misfire
cold engine
wall quenching

Question 3

What causes high Carbon Monoxide in the emission system?

Answer 3

power enrichment (cold operation/warm-up)
rich air/fuel ratio
clogged air filter
restricted PCV system

Question 4

What causes high Nitrogen Oxides in the emission system?

Answer 4

high intake & combustion temperature
faulty EGR system
high compression
lean air/fuel mixture

Question 5

What Pollutants does an exhaust system emit?

Answer 5

Hydrocarbon (HC)
Carbon Monoxide (CO)
Nitrogen Oxides (NOx)
Carbon Dioxide (CO2)

Question 6

What Emissions are being monitored & controlled in a gasoline engine?

Answer 6

Hydrocarbon (HC)
Carbon Monoxide (CO)
Nitrogen Oxides (NOx)

Question 7

At what temperature does Nitrogen Oxide (NOx) form?

Answer 7

1261 Celsius

Question 8

What is the purpose of injecting secondary air into the exhaust ports during warm up?

Answer 8

Heats up Catalytic Converter for Quicker light-off of the O2 sensor & converter

Question 9

What emission systems produce excess Hydrocarbon emissions?

Answer 9

Engine System, Fuel system & Delivery system

Question 10

What is a Catalyst?

Answer 10

Material that causes a chemical reaction without being part of the reaction

Question 11

What is the common name given to the fluid used in selective catalytic reduction system?

Answer 11

urea-based diesel exhaust fluid (DEF)

Question 12

Which emission is produced due to high combustion chamber temperatures?

Answer 12

Nitrogen Oxides (NOx)

Question 13

Which emissions system routes harmful gases from the engine’s crankcase back into the intake manifold for re-combustion?

Answer 13

PCV

Question 14

Which emission system educes nitrogen oxide emissions by recirculating a small amount of exhaust gas back into the engine’s combustion chamber?

Answer 14

EGR

Question 15

Which emission system reduces Hydrocarbon by supplying the catalytic converter with oxygen to allow it to heat up, and reach its light-off temperature more quickly?

Answer 15

AIR

Question 16

Which provinces in Canada do mandatory emission testing?

Answer 16

British Columbia & Ontario

Question 17

What is the 1 criteria that EVAP systems must meet before allowing a purge cycle?

Answer 17

Vehicle must be operating at a pre-determined temperature

Question 18

Under which driving condition would EGR flow into the engine be desirable.

Answer 18

driving speeds

Question 19

Where is the vehicle emission control information (VECI) decal located?

Answer 19

underside of the hood or on the radiator support frame

Question 20

What is the Hydrocarbon emission limit in Canada?

Answer 20

2g/hr

Question 21

How small of a leak can an enhanced EVAP system detect?

Answer 21

0.5 mm / 0.020 in.

Question 22

How does sludge form?

Answer 22

reaction between oil and condensed blowby

Question 23

How many oxygen atoms are joined with a nitrogen atom to form Nitrogen oxides?

Answer 23

variable number

Question 24

What effects the efficiency of a catalytic converter?

Answer 24

Temperature

Question 25

Which gases do Two-way Catalytic Converters reduce?

Answer 25

Hydrocarbons & Carbon Monoxide

Question 26

Which gases do Three-way Catalytic Converters reduce?

Answer 26

Hydrocarbons, Carbon Monoxide & Nitrogen Oxides

Question 27

What catalysts are used in the reduction bed of a catalytic Converter?

Answer 27

Either Platinum or Rhodium

Question 28

What catalysts are used in the oxidation bed of a catalytic Converter?

Answer 28

Both Platinum & Palladium

Question 29

Which Gas does Platinum or Rhodium primarily reduce?

Answer 29

Nitrogen Oxide (NOx)

Question 30

What is Diesel Exhaust Fluid (DEF) used for?

Answer 30

Reduces Nitrogen Oxides (NOx)

Question 31

When was the AIR system mandated in California?

Answer 31

1966

Question 32

When was the AIR system mandated in the US?

Answer 32

1968

Question 33

When was OBD-II mandated in the US?

Answer 33

1996

Question 34

When was OBD-II mandated in the Canada?

Answer 34

1998

Question 35

What is a Type A DTC?

Answer 35

Serious emission code triggered with only 1 occurrence

Question 36

What is a Type B DTC?

Answer 36

less serious emission code triggered on 2nd consecutive occurrence

Question 37

What is a Type C & Type D DTC?

Answer 37

Non-emission code triggering other warning lights (not MIL)

Question 38

What is the Stoichiometric Ratio?

Answer 38

14.7lbs of air to 1lb of fuel

Question 39

What is Air made of?

Answer 39

78% Nitrogen 21% Oxygen 1% Other Gases

Question 40

What is Gasoline made of?

Answer 40

Hydrocarbons

Question 41

What is the chemical reaction of engine combustion?

Answer 41

Hydrocarbons react with oxygen to produce water vapor & carbon dioxide, the Nitrogen passes through unchanged

Question 42

How is Smog formed?

Answer 42

Combination of Hydrocarbons, Nitrogen Oxides & Sunlight

Question 43

How are high Carbon Monoxide levels formed during the combustion process?

Answer 43

When not enough oxygen is present to oxidize the Carbon Atom into Carbon Dioxide (CO2)

Question 44

What is Particulate Matter made up of?

Answer 44

dust, soot & smoke

Question 45

What drivability issue can result from a charcoal canister that is filled with liquid?

Answer 45

rich running condition when purging

Question 46

What happens when the PCV is stuck in the open position?

Answer 46

rough idle & stalling

Question 47

What happens when the PCV is stuck in the closed position?

Answer 47

/

Question 48

Which emission gases are measured by a 2 gas analyzer?

Answer 48

Hydrocarbon & Carbon monoxide

Question 49

Which emission gases are measured by a 4 gas analyzer?

Answer 49

Hydrocarbon, Carbon Monoxide, Carbon Dioxide & Oxygen

Question 50

Which emission gases are measured by a 5 gas analyzer?

Answer 50

Hydrocarbon, Carbon Monoxide, Carbon Dioxide, Oxygen & Nitrogen Oxides

Question 51

When performing a catalytic converter diagnosis, what is the minimum temperature in which the converter can be accurately tested?

Answer 51

260 Celsius

Question 52

What is an indication of EGR system malfunction?

Answer 52

no-start, surging or stalling

Question 53

What happens to the opening of a PCV valve, when the intake vacuum Increases?

Answer 53

spring valve moves up, decreasing the opening

Question 54

What happens to the opening of a PCV valve, when the intake vacuum decreases?

Answer 54

spring valve moves down, increasing the opening