Diesel Engine Performance 2 Exam
Questions & Answers (Grade A+)
An engine had a fault code for high crankcase pressure and its
power was derated. Technician A says that the crankcase filter could
have frozen when exposed to extreme cold conditions. Technician B
says that a frozen filter would likely blow engine gaskets and seals
rather than cause a derate condition. Who is correct? -
correct answer ✅Tech A
Technician A says that a throttle plate on a late-model diesel engine
helps increase the exhaust temperatures for the exhaust
aftertreatment catalysts. Technician B says that diesel air intake is
not throttled. Who is correct? -
correct answer ✅Tech A
What happens to the mass of intake airflow taken into an engine
when the exhaust gas recirculation is enabled?
Nothing happens.
The mass increases.
The mass decreases.
The mass becomes cooler. -
correct answer ✅Mass decreases
,Diesel Engine Performance 2 Exam
Questions & Answers (Grade A+)
Which of the following methods can best detect a leaking air intake
system?
Inspecting the system visually
Spraying intake piping and joints with soap and water while the
engine is running
Using ether while the engine is running, then listening for engine
speed increase at leak points
Checking for silica with a lube oil analysis -
correct answer ✅Checking for silica with a lube oil analysis
Technician A says that electric intake heaters are used to reduce
cold-start and warm-up emissions. Technician B says that intake air
heaters help to shorten the cranking time of a cold engine. Who is
correct? -
correct answer ✅Both
Technician A says that it is acceptable practice to clean air filters
using compressed shop air. Technician B says that it is better to
clean air filters by dropping or lightly tapping the filter against the
shop floor. Who is correct? -
correct answer ✅Tech A
, Diesel Engine Performance 2 Exam
Questions & Answers (Grade A+)
Which of the following instruments is best used to measure air inlet
restrictions?
Vacuum gauge
0-5 psi (0-34 kPa) gauge
Water manometer
Mercury manometer -
correct answer ✅Water manometer
Which of the following air intake systems will best preclean dirt and
water from the air intake of an on-highway, diesel-powered
vehicle?
Front-mounted air inlet
Ram air induction
Composite intake
Side-mounted air inlet -
correct answer ✅Side-mounted air inlet
Questions & Answers (Grade A+)
An engine had a fault code for high crankcase pressure and its
power was derated. Technician A says that the crankcase filter could
have frozen when exposed to extreme cold conditions. Technician B
says that a frozen filter would likely blow engine gaskets and seals
rather than cause a derate condition. Who is correct? -
correct answer ✅Tech A
Technician A says that a throttle plate on a late-model diesel engine
helps increase the exhaust temperatures for the exhaust
aftertreatment catalysts. Technician B says that diesel air intake is
not throttled. Who is correct? -
correct answer ✅Tech A
What happens to the mass of intake airflow taken into an engine
when the exhaust gas recirculation is enabled?
Nothing happens.
The mass increases.
The mass decreases.
The mass becomes cooler. -
correct answer ✅Mass decreases
,Diesel Engine Performance 2 Exam
Questions & Answers (Grade A+)
Which of the following methods can best detect a leaking air intake
system?
Inspecting the system visually
Spraying intake piping and joints with soap and water while the
engine is running
Using ether while the engine is running, then listening for engine
speed increase at leak points
Checking for silica with a lube oil analysis -
correct answer ✅Checking for silica with a lube oil analysis
Technician A says that electric intake heaters are used to reduce
cold-start and warm-up emissions. Technician B says that intake air
heaters help to shorten the cranking time of a cold engine. Who is
correct? -
correct answer ✅Both
Technician A says that it is acceptable practice to clean air filters
using compressed shop air. Technician B says that it is better to
clean air filters by dropping or lightly tapping the filter against the
shop floor. Who is correct? -
correct answer ✅Tech A
, Diesel Engine Performance 2 Exam
Questions & Answers (Grade A+)
Which of the following instruments is best used to measure air inlet
restrictions?
Vacuum gauge
0-5 psi (0-34 kPa) gauge
Water manometer
Mercury manometer -
correct answer ✅Water manometer
Which of the following air intake systems will best preclean dirt and
water from the air intake of an on-highway, diesel-powered
vehicle?
Front-mounted air inlet
Ram air induction
Composite intake
Side-mounted air inlet -
correct answer ✅Side-mounted air inlet
