Combustion and Emission Questions

What can high O2 levels in the exhaust indicate?

• A) Rich air-fuel mixture

• B) Low combustion efficiency

• C) High combustion temperature

• D) Complete combustion

What does low NO2 levels suggest about combustion temperature?

• A) High combustion temperature

• B) Low combustion temperature

• C) Complete combustion

• D) Perfect air-fuel ratio

Which component can cause high CO levels if malfunctioning?

• A) Oxygen sensor

• B) Catalytic converter

• C) Exhaust manifold

• D) Muffler

What can cause high HC levels besides misfires?

• Proper ignition timing

• Faulty spark plugs

• Clean air filter

• High combustion temperature

What does a rich air-fuel mixture mean?

• A) Too much air, not enough fuel

• B) Too much fuel, not enough air

• C) Perfect balance of air and fuel

• D) Low combustion temperature

What can low compression pressure result in?

• High NO2 levels

• Low NO2 levels

• High CO2 levels

• Low HC levels

What can high O2 levels in the exhaust indicate?

• Rich air-fuel mixture

• Low combustion efficiency

• Complete combustion

• High combustion temperature

What can cause too much fuel in the system?

• Oxygen sensor

• Too much fuel

• Carbon Dioxide (CO2)

• Faulty CAT

What is the primary product of complete combustion?

• Carbon Monoxide (CO)

• Hydrocarbons (HC)

• Carbon Dioxide (CO2)

• Nitrogen Oxides (NO2)

Which component is responsible for measuring oxygen levels?

• Oxygen sensor

• BCM

• Air/Flow sensor

• MAP sensor