Engine Performance Test Questions and Answers Rated A
The crankshaft and camshaft design and the location of
What is the firing order determined by?
the spark plug wires
When analyzing an ignition oscilloscope pattern, what are
firing lines
the tall vertical spikes on the chart referred to as?
What can you tell about a spark plug that has a long It is very likely to run hotter at the tip than a spark plug that
ceramic insulator path? has a shorter path.
What does an upward-sloping spark line usually indicate? A mechanical engine problem
An electronic spark tester has a specified gap that requires
25,000
a minimum of volts to fire.
What is a knock sensor used to detect? Abnormal combustion
A core of soft iron surrounded by a secondary winding of
Which of the following is the most accurate physical de-
very fine wires, which is surrounded by a primary winding
scription of an ignition coil?
of heavier wires
You're using a multimeter to test the resistance of a pickup
coil. What range of values would indicate that it's working 500 to 1,500 ohms
correctly?
What device is responsible for signaling the switching of
Trigger
the coil on and ott, or just on in most instances?
When checking for a no-start concern, you notice that an
engine has no spark. Technician A says to turn on the
ignition (engine ott) and, using a DMM, find out how
much battery voltage is available at the negative terminal tech b``
of the ignition coil. Technician B says the DMM reading
should fluctuate, indicating that the primary coil current is
being turned on and ott. Who is correct?
The operation of the waste-spark ignition system is being
discussed. Technician A says the spark that occurs on the
exhaust stroke is called the "waste spark" because it does
, Engine Performance Test Questions and Answers Rated A
no useful work, being used only as a voltage path for the
secondary winding of the ignition coil. Technician B says
tech b
even if there's only one defective spark plug wire or spark
plug, two cylinders may be attected. Who is correct?
Which ignition system test is being performed in the pho-
pickup coil resistance
tograph?
The electronics in the ignition coil and the powertrain
control module in a compression-sensing ignition system
on the compression stroke.
can detect which of the two companion (paired) cylinders
require higher voltage, which indicates the cylinder that's
You're working on a car with a TP sensor that contains four
It's a switch circuit used to signal that the vehicle is at idle.
wires. What does the fourth wire do?
What is the primary reason many port fuel-injected sys- To ensure there is a constant pressure drop across the
tems use a vacuum-controlled fuel-pressure regulator? injectors
What type of fuel pump is designed to force everything
Displacement pump
that enters the pump to leave it?
If you are testing fuel pump pressure and it is at zero, what
Defective fuel pump relay
could be a possible cause?
You determine that an output actuator driver is faulty.
The component and circuit it controls
What should you check?
A is designed to electrically replace the injector
in a circuit and to flash if the injector circuit is working noid light
correctly.
What does brake mean ettective pressure (BMEP) indi-
How well an engine uses its displacement to produce work
cate?
You need to check the injectors in a vehicle. What is the Measurement of the resistance of the coil inside and com-
first test you should conduct? pare it to factory specifications
inline filter
The crankshaft and camshaft design and the location of
What is the firing order determined by?
the spark plug wires
When analyzing an ignition oscilloscope pattern, what are
firing lines
the tall vertical spikes on the chart referred to as?
What can you tell about a spark plug that has a long It is very likely to run hotter at the tip than a spark plug that
ceramic insulator path? has a shorter path.
What does an upward-sloping spark line usually indicate? A mechanical engine problem
An electronic spark tester has a specified gap that requires
25,000
a minimum of volts to fire.
What is a knock sensor used to detect? Abnormal combustion
A core of soft iron surrounded by a secondary winding of
Which of the following is the most accurate physical de-
very fine wires, which is surrounded by a primary winding
scription of an ignition coil?
of heavier wires
You're using a multimeter to test the resistance of a pickup
coil. What range of values would indicate that it's working 500 to 1,500 ohms
correctly?
What device is responsible for signaling the switching of
Trigger
the coil on and ott, or just on in most instances?
When checking for a no-start concern, you notice that an
engine has no spark. Technician A says to turn on the
ignition (engine ott) and, using a DMM, find out how
much battery voltage is available at the negative terminal tech b``
of the ignition coil. Technician B says the DMM reading
should fluctuate, indicating that the primary coil current is
being turned on and ott. Who is correct?
The operation of the waste-spark ignition system is being
discussed. Technician A says the spark that occurs on the
exhaust stroke is called the "waste spark" because it does
, Engine Performance Test Questions and Answers Rated A
no useful work, being used only as a voltage path for the
secondary winding of the ignition coil. Technician B says
tech b
even if there's only one defective spark plug wire or spark
plug, two cylinders may be attected. Who is correct?
Which ignition system test is being performed in the pho-
pickup coil resistance
tograph?
The electronics in the ignition coil and the powertrain
control module in a compression-sensing ignition system
on the compression stroke.
can detect which of the two companion (paired) cylinders
require higher voltage, which indicates the cylinder that's
You're working on a car with a TP sensor that contains four
It's a switch circuit used to signal that the vehicle is at idle.
wires. What does the fourth wire do?
What is the primary reason many port fuel-injected sys- To ensure there is a constant pressure drop across the
tems use a vacuum-controlled fuel-pressure regulator? injectors
What type of fuel pump is designed to force everything
Displacement pump
that enters the pump to leave it?
If you are testing fuel pump pressure and it is at zero, what
Defective fuel pump relay
could be a possible cause?
You determine that an output actuator driver is faulty.
The component and circuit it controls
What should you check?
A is designed to electrically replace the injector
in a circuit and to flash if the injector circuit is working noid light
correctly.
What does brake mean ettective pressure (BMEP) indi-
How well an engine uses its displacement to produce work
cate?
You need to check the injectors in a vehicle. What is the Measurement of the resistance of the coil inside and com-
first test you should conduct? pare it to factory specifications
inline filter
