EGR System Quiz

What does the EGR system feed into the intake manifold?

• Fresh air

• Exhaust gases

• Fuel

• Water vapor

What is the effect of feeding exhaust gases back into the intake manifold?

• Increases combustion temperature

• Increases NOx levels

• Lowers combustion temperature

• Increases air-fuel ratio

What is the role of the spring-loaded plunger in early EGR systems?

• To increase fuel flow

• To block the flow of gases through the orifice

• To increase air intake

• To reduce engine temperature

What was the design change in EGR systems due to the limitations of early systems?

• Use of only exhaust back pressure

• Use of both exhaust back pressure and manifold vacuum

• Use of only manifold vacuum

• Use of electronically controlled valves

What is the main component that blocks the flow of gases in early EGR systems?

• Throttle valve

• Plunger

• Orifice

• Manifold vacuum

What gases are collectively known as NOx?

• NO and NO2

• NO2 and CO2

• NO and CO

• NO2 and O2

What is the function of the diaphragm in a positive exhaust back pressure EGR valve?

• To open the valve when exhaust pressure is high enough

• To close the valve when exhaust pressure is low

• To regulate the intake air

• To control the fuel injection

What do solenoid-operated valves control in the EGR system?

• The vacuum supplied to the EGR system

• The fuel supply to the engine

• The air intake to the engine

• The exhaust gas temperature

What does one solenoid do in a solenoid-operated EGR valve system?

• Applies the vacuum

• Controls the fuel injection

• Measures the exhaust gas temperature

• Regulates the intake air

What does the other solenoid do in a solenoid-operated EGR valve system?

• Vents the vacuum

• Controls the fuel injection

• Measures the exhaust gas temperature

• Regulates the intake air