Exam 32: Intake and Exhaust Systems

Variable intake manifolds are being discussed. Technician A says an intake manifold tuning (IMT)system uses a butterfly valve to divide the plenum into two small chambers at low speeds. At high engine speeds, the butterfly valve opens to form one large plenum chamber. Technician B says the intake manifold runner control (IMRC)system changes the path of air between long and short runners or between small-diameter and large-diameter runners according to engine speed. Who is correct?

Which statement concerning variable nozzle turbine turbochargers is false?

Normal engine vacuum on a normally aspirated engine at idle is between ____________________ in. Hg and ____________________ in. Hg.

Technician A says most turbochargers have their own, self-contained, lubrication system. Technician B says a turbocharger should not be operated at an engine oil pressure lower than 30 psi. Who is correct?

A turbocharged engine is running with 10 psi (69 kPa)of turbo boost. At what pressure is air being fed into the engine when the engine is operating at sea level?

A catalytic converter is being tested with a pyrometer. The outlet temperature is 100 degrees Fahrenheit higher than the inlet temperature. What is indicated?

Modern intake manifolds for engines with port fuel injection are typically made of die-cast aluminum or plastic.

Describe the construction of a muffler.

Intercoolers are radiators for the intake air.

The ____________________ cools the turbocharged air before it reaches the combustion chamber.

The number-one cause of turbocharger failure is __________________.

What is turbo lag?

The function of the air bypass valve in a modern supercharger is to ______.

The __________________ is a chart of the vacuum hose routings, vacuum source, and relative component locations for all emissions-related equipment.

Exhaust manifolds for most vehicles are made of cast or nodular iron.

Lack of lubrication and oil lag are major causes of turbocharger failure.

Describe the main purpose of a catalytic converter.

Technician A says engine vacuum is normally measured in inches of mercury (in. Hg). Technician B says a pressure gauge that is labeled psig will read 14.7 psi at sea level. Who is correct?

What is the first step in turbocharger inspection?

Generally, an engine designed for maximum torque and horsepower at high speeds has longer runners than one that provides high torque at lower speeds.