Question 1

A thermostat can fail in which way?
A) Stuck partially open
B) Stuck open
C) Stuck closed
D) Any of the above

Accepted Answer

A thermostat can fail in any of these ways. If it is stuck partially open, it may not allow the engine to warm up properly, leading to poor fuel economy and performance. If it is stuck open, the engine may not reach operating temperature at all, causing poor fuel economy, poor performance, and increased emissions. If it is stuck closed, the engine will overheat, potentially causing severe damage.

Question 2

A skewed thermostat means it is ________.
A) contaminated with coolant
B) missing the thermo wax in the heat sensor
C) working, but not at the correct temperature
D) not working

Accepted Answer

A skewed thermostat means that it is working, but not at the correct temperature.

Question 3

Coolant drained from the cooling system when replacing a thermostat or water pump should be ________.
A) reused
B) filtered and reinstalled after the repair
C) poured down a toilet
D) disposed of properly or recycled

Accepted Answer

Coolant drained from the cooling system should never be reused or poured down a toilet. It should be disposed of properly or recycled, as it can be harmful to the environment and wildlife. Many auto parts stores and service centers accept used coolant for recycling.

Question 4

A water pump can fail provide the proper amount of coolant flow through the cooling system if what has happened?
A) The coolant is leaking from the weep hole
B) The impeller blades are worn or slipping on the shaft
C) A bearing failure has caused the shaft to become loose
D) The bearing is noisy

Accepted Answer

If the impeller blades are worn or slipping on the shaft, the water pump will not be able to provide the proper amount of coolant flow through the system. The other options (coolant leaking from the weep hole, bearing failure causing a loose shaft, and noisy bearing) may indicate a problem with the water pump, but may not necessarily result in a failure to provide coolant flow.

Question 5

Intake manifold gaskets on a V-type engine can fail due to what factor?
A) Coolant damage
B) Fretting
C) Relative movement between the intake manifold and the cylinder head
D) All of the above

Accepted Answer

The intake manifold gaskets on a V-type engine can fail due to multiple factors. Coolant damage can occur if there is a leak in the cooling system, which can cause corrosion or erosion of the gasket over time. Fretting can occur due to vibrations and movement, which can cause the gasket to wear away or become damaged. Finally, relative movement between the intake manifold and the cylinder head can cause stress on the gasket, leading to failure. Therefore, all of the above factors can contribute to the failure of intake manifold gaskets on a V-type engine.

Question 6

A defective thermostat can cause the powertrain control module (PCM) to set what diagnostic trouble code (DTC)?
A) P0171
B) P0300
C) P0172
D) P0128

Accepted Answer

A defective thermostat can cause the engine to not reach operating temperature, which triggers the PCM to set the diagnostic trouble code P0128 (coolant thermostat malfunction). The other codes listed relate to other possible issues, but not specifically a malfunctioning thermostat.

Question 7

The engine is attached to the vehicle using ________.
A) engine blocks
B) motor mounts
C) engine cables
D) engine rods

Accepted Answer

The engine is typically attached to the vehicle using motor mounts, which are typically made of rubber or metal and are designed to absorb shock and engine vibration. Engine blocks are the main structural component of the engine itself, not the vehicle, and are not used to attach the engine to the vehicle. Engine cables and rods may be used in certain engine systems, but they are not typically used to attach the engine to the vehicle.

Question 8

The torque specification for many plastic intake manifolds are in what unit?
A) Pound-feet
B) Lb-ft per second
C) Pound-inches
D) Ft-lbs per minute

Accepted Answer

The torque specification for many plastic intake manifolds are in pound-inches.

Question 9

When replacing a timing belt, many experts and vehicle manufacturers recommend that what other part(s) should be replaced?
A) Water pump
B) Camshaft oil seal(s)
C) Tensioner assembly
D) All of the above

Accepted Answer

When replacing a timing belt, it is best to replace all the components that work together with the belt. The water pump and tensioner assembly are commonly replaced at the same time since they have a similar lifespan and may cause belt failure if not replaced. The camshaft oil seal may also need to be replaced if it shows signs of wear or leakage. Therefore, it is best to replace all of the above components together with the timing belt to ensure reliable and long-lasting engine performance.

Question 10

Hybrid electric vehicles usually require special engine oil of what viscosity?
A) SAE 10W-30
B) SAE 5W-30
C) SAE 0W-20
D) SAE 5W-40

Accepted Answer

Hybrid electric vehicles typically require engine oil with a low viscosity to maximize fuel efficiency and minimize friction. SAE 0W-20 is a common recommendation for this type of vehicle.

Question 11

Technician A uses a steel gasket scraper on aluminum engine parts. Technician B uses a plastic or wood scraper on aluminum engine parts. 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. Steel scrapers can damage and scratch aluminum engine parts, whereas plastic or wood scrapers are softer and less likely to cause damage.

Question 12

An intake manifold gasket has been replaced due to a vacuum leak. Which of the following steps uses a scan tool to complete the job?
A) Refilling the cooling system
B) Torquing the manifold bolts
C) Air cleaner check
D) Idle relearn

Accepted Answer

Idle relearn is necessary after replacing an intake manifold gasket because it affects the engine's idle speed and can cause drivability issues. A scan tool is required to perform the idle relearn procedure. Refilling the cooling system, torquing the manifold bolts, and checking the air cleaner do not require a scan tool.

Question 13

A vehicle has set DTC P0172, indicating a lean exhaust and a vacuum leak is suspected. This can be diagnosed by introducing ________ around the intake manifold gasket.
A) sprayed gasoline
B) propane
C) rock salt
D) shop air

Accepted Answer

Propane can be used to introduce a flammable gas near the suspected vacuum leak. If the engine rpm increases when the gas is introduced, it indicates that the leak is located in that area.

Question 14

On some engines equipped with a timing belt, the belt also may drive the ________.
A) power steering
B) alternator
C) AC compressor
D) water pump

Accepted Answer

The timing belt may also drive the water pump on some engines. This is because the water pump is typically located near the timing belt and driven by the same system to ensure proper engine cooling. While some engines may have accessories such as the power steering pump, alternator, or AC compressor driven by the timing belt, it is typically the water pump that is driven by the timing belt in addition to the camshaft and crankshaft.

Question 15

A hybrid electric vehicle has a feature that could allow the engine to start and run without warning. This feature is called ________.
A) battery save
B) self-start
C) idle stop
D) false off

Accepted Answer

The feature being described is known as "idle stop," which allows the engine to automatically turn off when the vehicle is stopped to save fuel. However, the engine may restart without warning if certain conditions are met (such as pressing the accelerator pedal).

Question 16

Some of the wiring under the hood of a late model vehicle is encased in bright orange covering. This indicates a ________.
A) high pressure air conditioning system
B) high voltage electrical system
C) high pressure hydraulic systems
D) None of these

Accepted Answer

The bright orange covering indicates a high voltage electrical system. It is used as a safety measure to warn technicians and others that it is dangerous to touch or work on this wiring without proper training and equipment.

Question 17

Technician A says to use lineman's gloves when servicing the high voltage system on hybrid electric vehicles. Technician B says that some hybrid vehicles require high-viscosity engine oil. 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 A is correct. Lineman's gloves are necessary when servicing the high voltage system on hybrid electric vehicles for the safety of the technician. Technician B is incorrect. Hybrid vehicles do not require high-viscosity engine oil specifically. Engine oil recommendations vary by vehicle make and model, and are not specifically related to hybrid technology.

Question 18

When changing a timing belt, it is recommended that the ________ also be replaced.
A) air intake hoses
B) air pump seal
C) front crankshaft seal
D) air filter

Accepted Answer

When changing a timing belt, it is recommended that the front crankshaft seal also be replaced to ensure a proper seal and prevent future leaks. The other options listed are not typically related to the timing belt replacement procedure.

Question 19

Coolant leaking from an intake manifold can evaporate fast enough to leave no trace of a leak.

Accepted Answer

Coolant leaking from an intake manifold can evaporate quickly and leave no visible trace of a leak, making it difficult to detect.

Question 20

A technician is preparing to do an oil change on a hybrid vehicle. What special precaution needs to be taken BEFORE performing this service?
A) Leave the hood closed when draining the oil
B) Do not lift the vehicle more than 12 inches off the floor
C) Make sure the ignition is "OFF" and the key is removed from the ignition switch
D) Disconnect any orange colored wiring harnesses

Accepted Answer

Before performing an oil change on a hybrid vehicle, the technician should make sure the ignition is "OFF" and the key is removed from the ignition switch. This will prevent the electric motor from turning on and causing any harm to the technician or the vehicle.

Quiz 6: In-Vehicle Engine Service

A thermostat can fail in which way?

A skewed thermostat means it is ________.

Coolant drained from the cooling system when replacing a thermostat or water pump should be ________.

A water pump can fail provide the proper amount of coolant flow through the cooling system if what has happened?

Intake manifold gaskets on a V-type engine can fail due to what factor?

A defective thermostat can cause the powertrain control module (PCM) to set what diagnostic trouble code (DTC) ?

The engine is attached to the vehicle using ________.

The torque specification for many plastic intake manifolds are in what unit?

When replacing a timing belt, many experts and vehicle manufacturers recommend that what other part(s) should be replaced?

Hybrid electric vehicles usually require special engine oil of what viscosity?

Technician A uses a steel gasket scraper on aluminum engine parts. Technician B uses a plastic or wood scraper on aluminum engine parts. Which technician is correct?

An intake manifold gasket has been replaced due to a vacuum leak. Which of the following steps uses a scan tool to complete the job?

A vehicle has set DTC P0172, indicating a lean exhaust and a vacuum leak is suspected. This can be diagnosed by introducing ________ around the intake manifold gasket.

On some engines equipped with a timing belt, the belt also may drive the ________.

A hybrid electric vehicle has a feature that could allow the engine to start and run without warning. This feature is called ________.

Some of the wiring under the hood of a late model vehicle is encased in bright orange covering. This indicates a ________.

Technician A says to use lineman's gloves when servicing the high voltage system on hybrid electric vehicles. Technician B says that some hybrid vehicles require high-viscosity engine oil. Which technician is correct?

When changing a timing belt, it is recommended that the ________ also be replaced.

Coolant leaking from an intake manifold can evaporate fast enough to leave no trace of a leak.

A technician is preparing to do an oil change on a hybrid vehicle. What special precaution needs to be taken BEFORE performing this service?