Question 1

The PCV system controls which exhaust emission(s)?&#10;A)HC&#10;B)CO&#10;C)NOx&#10;D)Both A and B

Accepted Answer

The Positive Crankcase Ventilation (PCV) system controls hydrocarbons (HC) and carbon monoxide (CO) emissions by recirculating crankcase gases back into the engine's combustion chamber to be burned off, thereby reducing the amount of HC and CO released into the atmosphere.

Question 2

All engines are equipped with a PCV valve.

Accepted Answer

Not all engines are equipped with a PCV (Positive Crankcase Ventilation) valve. Some older or specially designed engines may use different methods for managing crankcase pressure and ventilation.

Question 3

Technician A says that if the PCV valve were defective or clogged, the engine could idle rough. Technician B says that the engine may stall. Which technician is correct?&#10;A)Technician A only&#10;B)Technician B only&#10;C)Both technicians A and B&#10;D)Neither technician A nor B

Accepted Answer

Both technicians are correct because a defective or clogged PCV (Positive Crankcase Ventilation) valve can cause an engine to idle rough due to improper air-fuel mixture and can also lead to engine stalling by creating an imbalance in the engine's air-fuel ratio.

Question 4

A P0410 DTC indicates a problem with ________.&#10;A)The SAI solenoid&#10;B)The idle control system&#10;C)MAF airflow&#10;D)None of these

Accepted Answer

A P0410 Diagnostic Trouble Code (DTC) specifically relates to an issue with the Secondary Air Injection (SAI) system, which can involve components such as the SAI solenoid.

Question 5

Technician A says that the PCV system should create a slight pressure in the crankcase at idle. Technician B says that the PCV system should create a slight vacuum in the crankcase at 2,500 RPM. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Accepted Answer

The PCV (Positive Crankcase Ventilation) system is designed to create a slight vacuum in the crankcase, not pressure, to help remove gases and reduce the risk of explosion. This vacuum is maintained both at idle and at higher RPMs, making Technician B's statement correct.

Question 6

The SAI system is used to reduce which exhaust emission?&#10;A)CO&#10;B)NOx&#10;C)HC&#10;D)Both HC and CO

Accepted Answer

The Secondary Air Injection (SAI) system is designed to reduce exhaust emissions by injecting fresh air into the exhaust system, which helps in further combustion of unburned hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gases.

Question 7

Two technicians are discussing exhaust check valves used in SAI systems. Technician A says that they are used to prevent the output from the SAI pump from entering the intake manifold. Technician B says the check valves are used to keep the exhaust from entering the AIR pump. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Accepted Answer

Technician B is correct. The check valves in Secondary Air Injection (SAI) systems are used to prevent exhaust gases from entering the AIR pump, protecting it from damage.

Question 8

Where is the output of the AIR pump directed when the engine is cold?&#10;A)Air cleaner assembly&#10;B)Catalytic converter&#10;C)Exhaust manifold&#10;D)To the atmosphere

Accepted Answer

When the engine is cold, the AIR (Air Injection Reaction) pump directs air into the exhaust manifold to help burn off excess hydrocarbons and reduce emissions.

Question 9

An electric SAI pump is controlled by ________.&#10;A)Exhaust pressure&#10;B)Manifold vacuum&#10;C)A vacuum switch&#10;D)The PCM

Accepted Answer

The electric Secondary Air Injection (SAI) pump is typically controlled by the Powertrain Control Module (PCM), which manages the operation of the pump based on various engine parameters and conditions to reduce exhaust emissions.

Question 10

When checking for the proper operation of the AIR system using an exhaust gas analyzer, how much should the oxygen levels increase when the pump is allowed to function?&#10;A)10-20%&#10;B)1-4%&#10;C)Up to 30%&#10;D)5-10%

Accepted Answer

The oxygen levels in the exhaust should increase by 1-4% when the AIR (Air Injection Reactor) system pump is functioning properly, as it introduces additional air into the exhaust system to aid in the further combustion of unburned hydrocarbons.

Question 11

In what year did PCV system monitoring become mandatory?&#10;A)1996&#10;B)2004&#10;C)2000&#10;D)1988

Accepted Answer

The answer of In what year did PCV system monitoring...

Question 12

The electric AIR pump is energized for ________.&#10;A)Until the engine goes into closed loop&#10;B)No longer than 4 minutes&#10;C)Either A or B&#10;D)Neither A nor B

Accepted Answer

The answer of The electric AIR pump is energized for...

Deck 85: Positive Crankcase Ventilation and Secondary Air-Injection Systems