Engine Performance Test 2 Exam Questions & Answers (Grade A+).docx

Engine Performance Test 2 Exam
Questions & Answers (Grade A+)
All the following are factors that cause knock EXCEPT:
a.
hotspots in the cylinder
b.
carbon on the pistons
c.
forced air into the cylinders
d.
decreased compression ratio -
correct answer ✅d.
decreased compression ratio


Octane ratings are being discussed. Technician A says most modern
engines are designed to use regular grade gasoline. Technician B
says to use high octane gasoline only when an engine was designed
to use it. Who is correct?
a.
A only
b.
B only

,Engine Performance Test 2 Exam
Questions & Answers (Grade A+)
c.
both A and B
d.
neither A nor B -
correct answer ✅c.
both A and B


All the following statements are correct EXCEPT:
a.
During a Reid vapor test, fuel is heated to 100 degrees Fahrenheit
(38 degrees Celsius)
b.
Vapor pressure is measured in psi
c.
The more volatile a fuel is, the easier it will vaporize
d.
Tetraethyl lead is added to gasoline to decrease the vapor pressure
-
correct answer ✅d.
Tetraethyl lead is added to gasoline to decrease the vapor pressure

,Engine Performance Test 2 Exam
Questions & Answers (Grade A+)

Methanol can be made from ______.
a.
wood
b.
coal
c.
natural gas
d.
All the answers are correct. -
correct answer ✅d.
All the answers are correct.


All of the following are aromatic hydrocarbons EXCEPT:
a.
benzene
b.
xylene
c.
kerosene

, Engine Performance Test 2 Exam
Questions & Answers (Grade A+)
d.
toluene -
correct answer ✅c.
kerosene


Technician A says increasing the Reid vapor pressure (RVP) will help
the engine start easier in cold weather. Technician B says increasing
the RVP will increase the possibility of fuel boiling (vapor lock) in
summer driving. Who is correct?
a.
A only
b.
B only
c.
both A and B
d.
neither A nor B -
correct answer ✅c.
both A and B


Excessive alcohol in the fuel may cause ______.