Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
Complete combustion requires what? -
correct answer ✅Correct amount of air and fuel, mixed in a sealed
container, shocked with the correct amount of heat.
Ignition systems do what? -
correct answer ✅Supplies properly timed, high-voltage spark,
under all operating conditions
Two types of ignition systems? -
correct answer ✅Distributor (DI) and distributor less (DSI)
Purposes of ignition system: -
correct answer ✅Generate enough heat to ignite mixture,
maintain spark long enough for total combustion of fuel, must
deliver the spark at the correct time
For maximum power: -
correct answer ✅combustion should be present when piston is at
10 to 23 degrees ATDC (after top dead center)
,Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
At higher engine speed rpm timing must what? -
correct answer ✅Advance
Light loads require timing ______. -
correct answer ✅Advance
Heavy loads require engine ______. -
correct answer ✅Retard
Ignition timing refers to ______. -
correct answer ✅The precise time spark occurs.
Ignition timing is reference to the position of ________ in relation
to crankshaft roatation. -
correct answer ✅Cylinder 1
To supply spark at the correct time each cylinder fires in a specific
_______ every 720 degrees, this is called a firing _______. -
correct answer ✅Order
,Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
Why must the spark timing begin earlier as engine speed increases?
-
correct answer ✅Spark timing must begin earlier as engine speed
increases because the time to generate the spark is constant. As
engine speed increases, the spark has to be delivered earlier to
account for the decreased time available before the piston reaches
TDC.
Computerized ignition sensors receive input from what? -
correct answer ✅Engine temp, engine speed, manifold vacuum,
throttle position, intake air temp, and other sensors
A typical fuel systems includes what components? -
correct answer ✅Fuel tank, lines, filter, and a pump
What maintains system pressure? -
correct answer ✅Pressure regulator
What does the (fuel) pressure do? -
correct answer ✅Generates the spraying force to inject the fuel
, Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
Types of fuel injection: -
correct answer ✅Throttle body, central point fuel injection, port
fuel injection, and gasoline direct injection
Electronic fuel ignition systems are ________ controlled. -
correct answer ✅Computer
Ideal air-fuel ratio for most conditions is what? -
correct answer ✅14.7:1
More air than ideal is called? -
correct answer ✅Lean
More fuel than ideal is called? -
correct answer ✅Rich
Emission control systems do what? -
correct answer ✅Reduce pollutants
Systems Exam Questions & Answers
(Grade A+)
Complete combustion requires what? -
correct answer ✅Correct amount of air and fuel, mixed in a sealed
container, shocked with the correct amount of heat.
Ignition systems do what? -
correct answer ✅Supplies properly timed, high-voltage spark,
under all operating conditions
Two types of ignition systems? -
correct answer ✅Distributor (DI) and distributor less (DSI)
Purposes of ignition system: -
correct answer ✅Generate enough heat to ignite mixture,
maintain spark long enough for total combustion of fuel, must
deliver the spark at the correct time
For maximum power: -
correct answer ✅combustion should be present when piston is at
10 to 23 degrees ATDC (after top dead center)
,Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
At higher engine speed rpm timing must what? -
correct answer ✅Advance
Light loads require timing ______. -
correct answer ✅Advance
Heavy loads require engine ______. -
correct answer ✅Retard
Ignition timing refers to ______. -
correct answer ✅The precise time spark occurs.
Ignition timing is reference to the position of ________ in relation
to crankshaft roatation. -
correct answer ✅Cylinder 1
To supply spark at the correct time each cylinder fires in a specific
_______ every 720 degrees, this is called a firing _______. -
correct answer ✅Order
,Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
Why must the spark timing begin earlier as engine speed increases?
-
correct answer ✅Spark timing must begin earlier as engine speed
increases because the time to generate the spark is constant. As
engine speed increases, the spark has to be delivered earlier to
account for the decreased time available before the piston reaches
TDC.
Computerized ignition sensors receive input from what? -
correct answer ✅Engine temp, engine speed, manifold vacuum,
throttle position, intake air temp, and other sensors
A typical fuel systems includes what components? -
correct answer ✅Fuel tank, lines, filter, and a pump
What maintains system pressure? -
correct answer ✅Pressure regulator
What does the (fuel) pressure do? -
correct answer ✅Generates the spraying force to inject the fuel
, Chapter 24 Engine Performance
Systems Exam Questions & Answers
(Grade A+)
Types of fuel injection: -
correct answer ✅Throttle body, central point fuel injection, port
fuel injection, and gasoline direct injection
Electronic fuel ignition systems are ________ controlled. -
correct answer ✅Computer
Ideal air-fuel ratio for most conditions is what? -
correct answer ✅14.7:1
More air than ideal is called? -
correct answer ✅Lean
More fuel than ideal is called? -
correct answer ✅Rich
Emission control systems do what? -
correct answer ✅Reduce pollutants
