Auto Fundamentals: Chapter 15 Review

Which of the following is not a purpose of the engine exhaust system?

• Maintain as much back pressure as possible.

• Reduce as much exhaust noise as possible.

• Route exhaust gases away from the engine and vehicle.

• Keep exhaust gases from entering the passenger compartment.

All of the following statements about exhaust system back pressure are true, except:

• A. excessive back pressure can reduce engine power and fuel mileage.

• B. back pressure occurs when the exhaust gas flow is restricted.

• C. complete lack of back pressure can cause exhaust valves to burn.

• D. excessive back pressure obstructs cylinders from clearing themselves during the exhaust stroke.

Modern factory cast iron exhaust manifolds are designed with tubes of equal length to make use of the exhaust (a)   effect.

• self-canceling

• scavenging

• reverse-flow

• equalizing

Where is double-wall construction used in the exhaust system?

• Exhaust pipes.

• Mufflers.

• Resonators.

• Tailpipes.

A catalytic converter is placed in the exhaust system before the muffler to (a)   .

• deaden sound

• silence resonance

• clean exhaust gases

• increase the scavenging effect

A resonator is used to .

• reduce exhaust sounds
• force air into the catalytic converter

• prevent exhaust back pressure

• cool the exhaust gasses

Exhaust system hangers perform all of the following functions, except:

• A. shock protection and sound deadening.

• B. hold the exhaust system rigidly against the surface of the vehicle body or frame.

• C. withstand exhaust system heat and road debris.

• D. suspend and support the exhaust system under the vehicle.

Which of the following are used to keep the catalytic converter from igniting flammable materials under the vehicle?

• Resonators

• Double-walled pipes

• Cast-iron headers

• Heat shields

A _____ exhaust connector uses a ball seal on one side only and allows some flexing.

• flat-surface

• semi-ball

• full-ball

• pipe-to-pipe

Which of the following devices is not attached to a modern vehicle’s exhaust system?

• Air injection nozzles.

• Exhaust temperature sensors.

• Two or more oxygen sensors.

• Mass airflow sensor.