Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1)
A turbocharged engine suffers from spark knock, or pinging. This could be caused by:
1)
A)
The turbo wastegate opening too soon or stuck open
B)
A restricted turbocharger oil return line
C)
An exhaust leak at the turbine inlet
D)
An EGR problem
2)
Technician A says thin oil or varnish deposits on a throttle body can cause hard cold starting and
other driveability problems. Technician B says some throttle bodies are manufactured with special
coatings and should not be cleaned. Which technician is correct?
2)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
C
3)
Technician A says the throttle position sensor on a vehicle equipped with electronic engine controls
performs the same function as the accelerator pump on a vehicle with a carburetor and no
electronic controls. Technician B says an improperly operating throttle position sensor CAN NOT
cause a hesitation on acceleration concern. Which technician is correct?
3)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
A
4)
To check the resistance in a complete secondary circuit for one cylinder, you should begin by using
an ohmmeter to measure the resistance between which of the following points?
4)
A)
The spark plug center electrode to the cable terminal inside the distributor cap
B)
The spark plug terminal of a cable to the cable terminal inside the distributor cap
C)
The spark plug ground electrode to the cable terminal inside the distributor cap
D)
The spark plug terminal of a cable to the terminal at the other end of the cable
B
D
5)
If liquid gasoline is present in the evaporative emission canister it is necessary to check the
________.
5)
A)
Fuel vapor separator
B)
Fuel pump
C)
Evaporative system hoses
D)
Fuel lines
6)
When an engine cranks normally but will not start, which of the following ignition problems is
NOT a probable cause?
6)
A)
A short circuit in the distributor pickup coil
B)
A short circuit in the ground coil
C)
A secondary voltage leak
D)
An open circuit in a spark plug cable
7)
Applying air into a cylinder with the piston at TDC on the compression stroke is known as a
________.
7)
A)
Fuel cylinder test
B)
Cylinder leakage test
C)
Cylinder balance test
D)
Compression test
8)
Technician A says that you should install an O2 sensor with anti–seize compound on the threads.
Technician B says that you can clean an O2 sensor with carburetor choke–cleaning spray and
low–pressure compressed air. Which technician is correct?
8)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
9)
The tool of choice for retrieving DTCs on late model Chrysler produces is the:
9)
A)
Tech 2
B)
DRB II
C)
Tech 1
D)
NGS
10)
Technician A says that an EGR vacuum amplifier should apply about 10 in. Hg of vacuum to the
EGR valve with 2 to 4 in. Hg of vacuum at the amplifier signal port. Technician B says that if the
signal vacuum is removed (a broken hose, for example), the amplifier applies manifold vacuum to
the EGR valve continuously. Which technician is correct?
10)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
11)
After changing oil in a turbocharged engine, Technician A cranks the engine without starting it for
about 15 seconds to prime the turbo. Technician B fills the new oil filter with fresh oil to help prime
the turbo. Which technician is doing the job correctly?
11)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
12)
Which of the following is NOT a possible cause for a GM CHECK ENGINE lamp to flash erratically
or display unlisted codes?
12)
A)
Computer supply voltage lower than 12 volts
B)
Routing the CCC system wiring harness too closely to other engine wiring
C)
An open diode in the air conditioning compressor clutch circuit
D)
Radio frequency interference from the ignition system
13)
Which of the following is NOT a typical procedure associated with removing an intake manifold?
13)
A)
Disconnect air cleaner duct tubes
B)
Disconnect accelerator cable
C)
Drain engine oil
D)
Drain engine coolant
14)
Technician A says hard faults are addressed immediately by performing a pinpoint test.
Technician B says memory faults are isolated using pinpoints tests and are typically diagnosed
before moving on a hard fault concerns. Which technician is correct?
14)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
15)
When testing a converter–equipped car with a 4–gas exhaust analyzer, the O2 reading is above 4%.
This means that:
15)
A)
The air–fuel mixture is too lean
B)
The air pump is inoperative
C)
Ignition timing is retarded
D)
EGR is not operating
16)
Technician A says before doing a compression test you should bring the engine to operating
temperature. Technician B says before doing a compression test you should block the throttle wide
open. Which technician is correct?
16)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
17)
To test the operation of a power valve, manifold absolute pressure (MAP) sensor or mass air flow
(MAF) sensor, you:
17)
A)
Bring the engine to normal operating temperature, and quickly open the throttle while
watching the CO meter
B)
Monitor the CO meter at idle with the engine cold
C)
Block the throttle wide open, inject air into cylinder number one, and watch the CO reading
on the meter
D)
Monitor the CO meter at idle with the engine warm
18)
When an engine runs but backfires repeatedly, which of the following is NOT a common cause?
18)
A)
Wrong spark plug heat range
B)
Incorrect timing or spark advance
C)
Low–octane gasoline
D)
Ignition wire crossfire
19)
Technician A says that switched inputs that are pull–up circuits the voltage is sourced from the
PCM. Technician B says that switched inputs that are pull–up circuits the voltage is externally
sourced and applied to the PCM circuit. Which technician is correct?
19)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
20)
A spark plug with shiny yellow or tan deposits has:
20)
A)
Insulator glazing
B)
Detonation damage
C)
Mechanical damage
D)
Gap bridging
21)
Technician A says the OBD II EGR monitor activates when the engine is furs started and continues
until the engine is shut off. Technician B says that the PCM will immediately set a trouble code if a
lean shift is not detected during the function test. Which technician is correct?
21)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
22)
A digital signal is:
22)
A)
A varying voltage signal
B)
An on/off DC signal
C)
An AC signal
D)
None of the above
23)
Which of the following is NOT indicated by a “lean exhaust” trouble code?
23)
A)
Excessive vapor canister purging
B)
Intake air (vacuum) leaks
C)
An EGR problem
D)
An engine misfire
24)
You are testing a vehicle for a no start condition. All the injectors have 12 volts to them. You have
tested for injector pulses at all injectors with an injector test light and found that none of the
injectors are pulsing. The MOST likely cause would be:
24)
A)
Defective fuel pump
B)
Loss of ignition reference signal to the PCM
C)
Defective fuel injector driver in the PCM
D)
None of the above
B
25)
Technician A says you cannot use a modified spark plug (spark tester, or simulator) on a
breaker–point ignition. Technician B says you should use this kind of tester to check available
voltage on many electronic ignitions. Which technician is correct?
25)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
B
26)
Secondary cable resistance often results from:
26)
A)
Loose or corroded terminal connections
B)
Improper trigger device operation
C)
Shorted CKP sensor
D)
Low battery voltage
A
A
27)
A turbocharger is making a light, steady whistling sound that increases in frequency as the engine
accelerates. This probably indicates:
27)
A)
Damaged bearings
B)
A loose exhaust pipe or exhaust outlet elbow
C)
Normal operation of the turbo
D)
An intake air leak
28)
An infrared analyzer is to be used on a late–model car. Technician A says it measures CO as a
percentage and HC in parts per million. Technician B says it compares air from the tailpipe with
surrounding air. Which technician is correct?
28)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
29)
Technician A says modern engine analyzers often provide onscreen directions for connecting
cables. Technician B says an oscilloscope may be part of an engine analyzer. Which technician is
correct?
29)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
30)
Fuel ________ and ________ are checked when testing a fuel pump.
30)
A)
Pressure; Volume
B)
Volume; Octane
C)
Volatility; Octane
D)
Pressure; Volatility
31)
Engine speed is increased from idle to 2000 rpm. The vacuum gauge needle rises quickly but
returns slowly. Technician A says the ignition timing is late. Technician B says there is an exhaust
restriction. Which technician is correct?
31)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
32)
Technician A says that aftermarket air filters that use an oiled element can damage mass air flow
sensors. Technician B says that the oscilloscope is the best tool to test most mass air flow sensors
with. Which technician is correct?
32)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
33)
Most turbocharger failures result from:
33)
A)
Dirt
B)
Operation with leaded gasoline
C)
Excessive high–speed operations
D)
Excessive exhaust temperatures
34)
Technician A says that a leak on the outlet side of a supercharger will cause a rich mixture.
Technician B says that leakage between the mass airflow (MAF) sensor and the blower inlet will
cause a rich mixture. Which technician is correct?
34)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
35)
An engine with electronic fuel injection (EFI) cranks but will not start. This could be caused by a
problem with any of the following, EXCEPT:
35)
A)
A throttle position sensor
B)
An airflow sensor
C)
Fuel delivery pressure
D)
A coolant temperature sensor
36)
________ can cause distortion in the CO and HC readings.
36)
A)
Engine coolant temperature sensors
B)
Mass airflow sensors
C)
Throttle position sensors
D)
Oxygen sensors
37)
CO2 levels should typically be higher than:
37)
A)
2%
B)
4%
C)
6%
D)
8%
38)
Which tool would be the best tool to test an injector driver with?
38)
A)
“Noid” light
B)
Test light
C)
Scan tool
D)
DVOM
39)
Technician A says residual fuel pressure is NOT a concern on low–pressure throttle body injection
systems. Technician B says high–pressure EFI systems typically operate at a fuel pressure of 15 psi
(103 kPA). Which technician is correct?
39)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
40)
Rounded and worn electrodes indicate a spark plug is:
40)
A)
Splash fouled
B)
Worn out
C)
Too cold
D)
Ash fouled
41)
Technician A says that worn spots on the turbine or compressor blade tips of a turbocharger
indicate that the blades have been rubbing the housing. Technician B says that the worn spots on
the blade tips indicate bearing or shaft damage. Which technician is correct?
41)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
42)
A vacuum gauge reading at idle is steady, but three inches above normal. Technician A says the
ignition timing is over–advanced. Technician B says the piston rings are worn. Which technician is
correct?
42)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
43)
The vacuum gauge needle drops two inches from normal during a vacuum leak test. Technician A
says a valve is not seating. Technician B says the intake manifold is leaking. Which technician is
correct?
43)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
44)
The driver of a turbocharged vehicle reports a lack of power complaint. Technician A says the first
step in troubleshooting is to perform a visual inspection of the turbocharger. Technician B says the
concern could be caused by an air intake or exhaust restriction. Which technician is correct?
44)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
45)
When individual cylinder patterns are stacked one above the other in an oscilloscope display, it is
called a:
45)
A)
Parade pattern
B)
Shifted pattern
C)
Rastar pattern
D)
Superimposed pattern
46)
Technician A says that the parameters for setting a code are important for the technician to know.
Technician B says that knowing the parameters for setting a code is not important because when
the technician road tests the vehicle if the code does not come back then the vehicle has been
successfully repaired. Which technician is correct?
46)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
47)
A mechanical fuel pump is to be replaced. Technician A says to use gasket sealer on the pump
mounting gasket. Technician B says the pump rocker arm must bear to the high point of the
camshaft eccentric before removal. Which technician is correct?
47)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
48)
When deposits break loose from pistons and valves and hit plug insulators, it is called:
48)
A)
Pre–ignition
B)
Detonation
C)
Carbon fouling
D)
Splash fouling
49)
Variable resistors send ________ signals.
49)
A)
Digital
B)
Analog
C)
Frequency
D)
Binary
50)
An engine idles roughly. The engine idles smoothly when the EGR vacuum line is disconnected.
This probably means that:
50)
A)
The EGR valve diaphragm has failed
B)
The engine has an intake manifold air leak
C)
The EGR valve is leaking
D)
A vacuum control solenoid has failed
51)
Some electronic ignition systems use spark plug cables of which kind?
51)
A)
0.28–inch (7–mm) copper core
B)
0.31–inch (8–mm) TVRS conductor
C)
0.31–inch (8–mm) copper core
D)
0.31–inch (8–mm) silicon conductor
52)
The tool of choice for retrieving DTCs from late model Ford products is:
52)
A)
Tech 1
B)
Tech 2
C)
DRB II
D)
NGS
53)
Computer controlled output devices generally consist of:
53)
A)
Relays
B)
Solenoids
C)
Actuators
D)
All of the above
54)
Technician A says that a switched output can be tested with a test light. Technician B says that a
scan tool can often show if a switched output is working. Which technician is correct?
54)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
55)
In order to perform a fuel balance test it is necessary to know:
55)
A)
What the fuel pressure is prior to performing the test
B)
How the engine’s intake manifold is designed
C)
How the engine’s exhaust manifold is designed
D)
What the volumetric efficiency of the fuel pump is prior to the test
56)
Technician A says the most reliable way to test an ignition coil is to check the primary and
secondary winding resistance. Technician B says most manufacturers provide current draw
specifications and procedures for checking an ignition coil with an ammeter. Which technician is
correct?
56)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
57)
An infrared analyzer shows a high CO level for a certain engine. Technician A says the problem is
probably fuel related. Technician B says the problem is ignition related. Which technician is
correct?
57)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
58)
Technician A says pulling ignition wires can cause internal damage. Technician B says it is usually
NOT possible to visually detect internally damaged ignition wires. Which technician is correct?
58)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
59)
Technician A says that exhaust deposits on the turbo wastegate can cause it to stick. Technician B
says that exhaust deposits on the wastegate can cause high boost pressure. Which technician is
correct?
59)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
60)
Two adjacent cylinders have low compression readings. Technician A says the valves are sticking.
Technician B says there are carbon deposits. Which technician is correct?
60)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
61)
Which of the following sensors are not analog inputs?
61)
A)
AC On Input
B)
Throttle Position Sensor
C)
Engine Coolant Temperature Sensor
D)
Magnetic Vehicle Speed Sensor
62)
Technician A says that most turbocharger shafts have 0.003 to 0.006 inch (0.076 to 0.152 mm) radial
clearance. Technician B says that axial clearance is always slightly greater than radial clearance.
Which technician is correct?
62)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
63)
Computers can send output signals by ________.
63)
A)
Applying voltage to a circuit
B)
Applying ground to a circuit
C)
Alternately apply voltage and ground
D)
Any of the above
64)
An open PCV system filler cap is being cleaned. Technician A says it must be washed in a solvent
and left to dry. Technician B says it can be dried with compressed air. Which technician is correct?
64)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
65)
Stepper motors that are PCM controlled are controlled with what type of output signal?
65)
A)
Switched
B)
Pulse width modulation
C)
Digital
D)
None of the above
66)
Technician A says that switched inputs often can be tested using a scan tool. Technician B says that
switched inputs can be tested with a DVOM. Which technician is correct?
66)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
67)
A vacuum gauge reading held steady at five inches during a cranking vacuum test. Technician A
says there is no intake leakage. Technician B says the piston rings are probably good. Which
technician is correct?
67)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
68)
The most recognizable characteristic of a mechanical returnless fuel system is:
68)
A)
There is no fuel return line coming off the fuel rail and no visible pressure regulator
B)
The fuel injectors are operated mechanically
C)
The placement of a fuel pressure sensor on the fuel rail
D)
The mechanically operated fuel pressure regulator located in the fuel rail
69)
The HEI ignition is used by:
69)
A)
GM
B)
AMC
C)
Ford
D)
Chrysler
70)
Technician A says that the scan tool is the best tool to test the throttle position sensor with.
Technician B says that the oscilloscope is the best tool to test a throttle position sensor with. Which
technician is correct?
70)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
71)
An engine with electronic fuel injection (EFI) starts when cold and then stalls. The most likely
cause among the following is:
71)
A)
A blown fuse in the fuel pump relay circuit
B)
No residual fuel pressure
C)
An airflow sensor problem
D)
No signal from the distributor or the engine speed sensor
72)
To check a TBI solenoid injector, you can use:
72)
A)
An ohmmeter
B)
A stethoscope
C)
A timing light
D)
All of the above
73)
Air valve switching and bypass (diverter) functions can be controlled by:
73)
A)
A simple vacuum diaphragm
B)
Computer–controlled vacuum solenoids
C)
Air pressure and atmospheric pressure on opposite sides of a diaphragm
D)
All of the above
74)
Technician A says available voltage is the maximum voltage that the coil can deliver. Technician B
says the voltage needed to bridge the rotor air gap may be three to eight kilovolts, which is part of
required voltage. Which technician is correct?
74)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
75)
The ________ provides an interface between the vehicle’s computer and the test device used to
retrieve codes.
75)
A)
Data Link Connector (DLC)
B)
OBD II
C)
OBD I
D)
Standard Corporate Protocol (SCP)
76)
Auxiliary fans are used when testing vehicles on a dynamometer when the ambient air
temperature is greater than ________.
76)
A)
62 degrees F
B)
90 degrees F
C)
80 degrees F
D)
72 degrees F
77)
Which of the following CANNOT cause current draw at the ignition coil that is lower than
specifications?
77)
A)
Loose connections in the primary circuit
B)
An open circuit in the starting bypass circuit
C)
High resistance in the coil primary winding
D)
A discharged battery
78)
Which of the following is NOT a probable cause of high resistance in the ignition primary circuit?
78)
A)
A defective ballast resistor
B)
A bad coil
C)
High charging voltage
D)
A poor ground at the ignition module
79)
A vehicle has an inoperative electric fuel pump. An electrical test reveals there is adequate supply
voltage at the pump. Technician A says the fuel pump should be replaced. Technician B says the
fuel pump relay should be replaced. Which technician is correct?
79)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
80)
________ is a loosely defined term used to describe abnormal voltage levels on one circuit resulting
from electrical activity on a second circuit.
80)
A)
Electromagnetic induction
B)
Electrical saturation
C)
Electrical noise
D)
Ballast resistance
81)
If regulated fuel pressure is ABOVE specifications, you may have:
81)
A)
A leaking fuel pump
B)
A restricted fuel return line
C)
A leaking injector nozzle
D)
A clogged fuel filter
82)
Technician A says the PCM typically recognizes when an input signal is not being furnished.
Technician B says that most PCM related faults cause the PCM to illuminate the MIL. Which
technician is correct?
82)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
83)
With an engine running at fast idle, the air delivery hose is pinched closed and a light popping
sound is heard. This indicates that:
83)
A)
A check valve is leaking
B)
The relief valve is opening properly
C)
The diverter valve is blocked
D)
The air pump is leaking internally
84)
The solid–state distributor is NOT tested for:
84)
A)
Shaft wear
B)
Cam wear
C)
Bushing wear
D)
All of the above
85)
A fuel pump’s delivery volume does not match the manufacturer’s specifications. Technician A
says there may be a fuel line restriction. Technician B says the pump must be replaced. Which
technician is correct?
85)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
86)
Portable five–gas analyzers are very useful in obtaining baseline readings for which emission?
86)
A)
NOx
B)
O2
C)
CO
D)
HC
87)
At cruising speed, turbocharger noise suddenly decreases and the engine emits smoke. This
probably indicates that:
87)
A)
The air filter is restricted
B)
The turbo has gone south
C)
The wastegate is stuck open
D)
An intake air leak has developed
88)
A PCV system is operating incorrectly. Technician A says adjust the system. Technician B says any
defective parts must be replaced. Which technician is correct?
88)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
89)
Low O2 and high CO levels can be caused by:
89)
A)
Restricted air filter
B)
Defective coolant sensor
C)
Rich mixture
D)
Any of the above
90)
A(n) ________ test is used to check the integrity of the EVAP system.
90)
A)
Enhanced OBD II
B)
EVAP Volume
C)
Purge
D)
EVAP Pressure
91)
Most automotive temperature sensors are ________.
91)
A)
Digital
B)
Negative temperature coefficient
C)
Switches
D)
Positive temperature coefficient
92)
Technician A says that you check radial bearing clearance on a shaft by mounting a dial indicator to
contact the end of the shaft. Technician B says that you check axial clearance by mounting a dial
indicator to contact the side of the shaft through the center housing. Which technician is correct?
92)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
93)
Technician A says a triggering device may be located in the distributor or mounted on the engine
block. Technician B says the primary circuit does not energize until the module receives a
verifiable engine speed signal. Which technician is correct?
93)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
94)
Which of the following parts, or areas, of a distributor does NOT require silicone grease?
94)
A)
On the trigger wheel teeth
B)
On the rotor tip and cap terminals
C)
On primary connectors for the pickup coil
D)
Between a distributor–mounted module and its base in he distributor
95)
Technician A says today’s vehicles typically use several computers to control engine functions such
as ignition, fuel and emissions components. Technician B says the BASIC TESTING PRINCIPLES
of all engine control systems are the same no matter how many vehicle functions the system
manages. Which technician is correct?
95)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
96)
Technician A says that you can test an O2 sensor with an ammeter. Technician B says that you can
test an O2 sensor with a high–impedance voltmeter. Which technician is correct?
96)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
97)
An oscilloscope secondary parade pattern allows you to compare:
97)
A)
Peak firing voltage among cylinders
B)
Dwell variation
C)
Carbon tracks in the distributor cap
D)
Voltage reserve and required voltage
98)
Technician A says only canisters that use oiled foam or fiberglass filters located in the bottom of the
canister need to be replaced periodically. Technician B says the frequency at which filter
replacement is necessary depends on how the vehicle is driven. Which technician is correct?
98)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
99)
A polyethylene fuel tank is very dirty. Technician A says the tank should be steam cleaned.
Technician B says the tank should be replaced. Which technician is correct?
99)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
100)
Technician A says most cylinder power analyzers are NOT compatible with distributorless ignition
systems. Technician B says the only way to perform a cylinder power balance test on a vehicle
equipped with a distributorless ignition is with a special analyzer that is compatible with
distributorless ignition systems. Which technician is correct?
100)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
101)
Technician A says that an EGR valve with a built–in backpressure transducer can be tested by
applying manifold vacuum to the valve at idle and watching for valve stem movement. Technician
B says that an EGR system with a backpressure transducer can be tested by disconnecting the
vacuum–control solenoid at idle. Which technician is correct?
101)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
102)
A weak battery or high terminal resistance ________ available voltage and restricts current, which
reduces ignition performance.
102)
A)
Increases
B)
Eliminates
C)
Reduces
D)
Shorts out
103)
The fuel pump module on mechanical returnless fuel systems is typically located:
103)
A)
Under the instrument panel near the PCM
B)
Inside the fuel tank
C)
On the fuel rail
D)
Under the hood fastened to the bulkhead
104)
A knocking sound is heard from an air pump during an air injection system test. Any of the
following could cause this EXCEPT:
104)
A)
A defective anti–backfire valve
B)
A loose pump–mounting bracket
C)
A glazed drive belt
D)
A leaking hose
105)
Four gas analyzers measure:
105)
A)
HC, O2, CO, CO2
B)
HC, O2, NOx, CO2
C)
HC, NOx, CO, CO2
D)
All of the above
106)
Which of the following BEST describes a proper diagnostic approach?
106)
A)
Retrieve memory codes, perform pinpoint tests, retrieve hard fault codes, and perform a
visual inspection
B)
Retrieve memory codes, retrieve hard fault codes, perform a visual inspection, and perform a
pinpoint test
C)
Retrieve hard fault codes, perform a visual inspection, perform pinpoint tests, and retrieve
memory codes
D)
Perform a visual inspection, retrieve memory codes, retrieve hard fault codes and perform
pinpoint tests
107)
There are two types of engine power balance tests:
107)
A)
Compression and injector/carburetor
B)
Cylinder power and compression
C)
Injector and carburetor
D)
Cylinder power and injector/carburetor
108)
Technician A says that during the OBD II I/M test if the MIL light is on the vehicle will fail the test.
Technician B says that if the MIL light is on the vehicle will only fail the test if the associated code is
emissions related. Which technician is correct?
108)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
109)
An engine seems to be running out of gas after it is at operating temperature. Technician A says
the air cleaner snorkel damper may be letting hot air into the air cleaner. Technician B says the fuel
pump may be bad. Which technician is correct?
109)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
110)
Black exhaust smoke from a turbocharged engine can indicate:
110)
A)
A clogged intake air filter
B)
Coolant leakage into the cylinders
C)
Leaking oil seals in the turbocharger
D)
Low boost pressure
111)
The prefix letter “P” of an OBD II DTC indicates:
111)
A)
Powertrain
B)
Power brakes
C)
Power steering
D)
PCM
112)
In an oscilloscope pattern, the peak voltage at the time the spark plug ionizes and first fires is
usually called the:
112)
A)
Burn time
B)
Firing line
C)
Dwell period
D)
Spark line, or period
113)
An engine computer must have ________ to record and store an intermittent trouble code.
113)
A)
PROM memory
B)
Long–term memory
C)
Hard memory
D)
RAM memory
114)
A turbocharger is making a grinding or rubbing sound. This probably indicates:
114)
A)
A loose wastegate actuator
B)
A loose exhaust outlet elbow
C)
Bearing damage
D)
A restricted oil return line
115)
Compression was low on the first stroke of a compression test. It built up but did not reach
specifications. Technician A says the valves are sticking. Technician B says the rings are worn.
Which technician is correct?
115)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
116)
Technician A says that an air pump can be rebuilt in the shop. Technician B says that an air pump
filter fan, relief valve, or outlet tube can be easily replaced. Which technician is correct?
116)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
117)
If HCs are high but CO is near normal when performing an exhaust analysis. This indicates that
the vehicle is running too:
117)
A)
Stoichiometric
B)
Lean
C)
Rich
D)
None of the above
118)
Before opening a fuel line for testing or service it is necessary to:
118)
A)
Electrically cycle the fuel injectors to run the fuel out of the lines
B)
Relieve the fuel pressure from the system
C)
Remove the fuel filter and install a fuel shut–off valve
D)
Drain the fuel from the tank and lines
119)
A fuel pump was checked and the breather hole shows signs of gas leakage. Technician A says the
pump should be replaced. Technician B says it would be a good idea to change the oil and oil filter.
Which technician is correct?
119)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
120)
Which tool listed below would be the best tool to test a digital signal with?
120)
A)
Oscilloscope
B)
Test light
C)
DVOM
D)
Scan tool
121)
A blackened, soot–covered spark plug may be caused by:
121)
A)
A rich air–fuel mixture
B)
High compression due to combustion chamber deposits
C)
Lead additives in gasoline
D)
A heat range that is too hot
122)
Low pressure Throttle Body Injection (TBI) systems typically operate at ________ psi.
122)
A)
5 to 10
B)
10 to 15
C)
15 to 20
D)
20 to 25
123)
Technician A says that to test most electronic throttle actuators the technician must use a scan tool.
Technician B says that most electronic throttle actuators can be tested without the use of a scan tool.
Which technician is correct?
123)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
124)
Technician A says that you need a vacuum gauge to test boost pressure. Technician B says that you
can use a radiator pressure tester to check wastegate actuator operation. Which technician is
correct?
124)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
125)
A potentiometer sensor almost always has a connector with:
125)
A)
1 wire
B)
2 wires
C)
3 wires
D)
4 wires
126)
Technician A says that a pulse air valve can be tested with a large rubber bulb, or syringe.
Technician B says intake air pulses can be checked at a pulse air valve with the engine running.
Which technician is correct?
126)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
127)
An engine runs, but one cylinder misfires continually. Which of the following is NOT a probable
cause?
127)
A)
A bad distributor cap terminal
B)
An open circuit in the spark plug cable
C)
An open circuit in the distributor pickup coil
D)
A fouled spark plug
128)
A burned air injection hose upstream from a check valve usually indicates:
128)
A)
A leaking check valve
B)
Excessive air pump pressure
C)
A stuck relief valve
D)
A broken diverter valve
129)
An engine with electronic fuel injection (EFI) has no fast idle. The most likely cause among the
following is:
129)
A)
A throttle–position sensor problem
B)
A vapor canister purge problem
C)
A fuel pressure problem
D)
A coolant or air–temperature sensor problem
130)
Exhaust gas recirculation (EGR) on a gasoline engine should NOT operate underall of the
following conditions EXCEPT:
130)
A)
Deceleration
B)
Wide–open throttle
C)
Cruising speed between 30 and 50 mph
D)
Cold–engine warm–up
131)
Technician A says some fuel injector cleaning procedures call for removing the injectors from the
fuel rail or throttle body. Technician B says fuel injector cleaning solvents can affect injector coil
wire insulation if used improperly. Which technician is correct?
131)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
132)
Fuel pressure is being checked on a domestic vehicle equipped with electronic fuel injection and an
electric fuel pump. Technician A says the fuel pressure should increase as engine speed increases.
Technician B says when the engine is turned off it is normal for the fuel pressure to quickly drop to
zero. Which technician is correct?
132)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
133)
Which of the following correctly lists the order of basic steps performed when doing an exhaust gas
analysis test?
133)
A)
Connect the exhaust analyzer according to manufacturer‘s instructions, Calibrate the analyzer
as required, Watch the meter and record the readings, Disconnect the plug and air injection
outlet line if applicable
B)
Connect the exhaust analyzer according to manufacturer‘s instructions, Calibrate the analyzer
as required, Record readings at 2,500 rpm, Record readings at idle
C)
Connect the exhaust analyzer according to manufacturer’s instructions, Record readings at
2,500 rpm, Calibrate the analyzer as required, Record readings at idle
D)
Connect the exhaust analyzer according to manufacturer’s instructions, Take all readings with
the air cleaner installed, Record readings at idle, Record readings at 2,500 rpm
134)
An engine equipped with a backpressure EGR system surges at cruising speed. Technician A says
that this can be caused by a defective backpressure transducer. Technician B says that this can be
caused by a concern with the vacuum–bleed solenoid. Which technician is correct?
134)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
135)
A spark plug heat range that is too hot can cause:
135)
A)
Gap bridging
B)
Splash fouling
C)
Detonation
D)
Oil fouling
136)
If an oscilloscope pattern is upside down, ignition coil polarity may be reversed, or:
136)
A)
The ignition coil is shorted
B)
Distributor pickup coil polarity is reversed
C)
The ignition module has a high–resistance ground connection
D)
The oscilloscope primary leads may be connected backwards
137)
Which of the following is the most likely location for a PCV valve?
137)
A)
Throttle body
B)
The exhaust manifold
C)
Upper intake plenum
D)
Valve cover
138)
A turbocharged engine suffers from high oil consumption. This could be caused by all of the
following EXCEPT:
138)
A)
Worn rings or valve guides
B)
A restricted turbocharger oil return line
C)
The wastegate not opening
D)
Excessive blow–by
139)
A normal vacuum reading varies between:
139)
A)
12 and 15 inches (305 and 380 mm) of mercury
B)
5 and 10 inches (125 and 254 mm) of mercury
C)
30 and 35 inches (762 and 889 mm) of mercury
D)
18 and 22 inches (460 and 560 mm) of mercury
140)
Technician A says replacing a converter requires special tools and procedures. Technician B says
heat shields need not be reinstalled when replacing a catalytic converter. Which technician is
correct?
140)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
141)
Most state certified analyzers require gas calibrations and leak test be performed every ________
day(s).
141)
A)
Seven
B)
Two
C)
Three
D)
One
142)
Technician A says most electric in–tank fuel pumps are equipped with a fuel filter sock. Technician
B says it is rarely necessary to replace the fuel filter(s) on vehicles equipped with electric pumps.
Which technician is correct?
142)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
143)
The fuel rail pressure sensor provides the ________ with fuel pressure data on ________ fuel
systems.
143)
A)
PCM; mechanical–returnless
B)
Fuel pressure regulator, mechanical–returnless
C)
Fuel pressure regulator; electronic–returnless
D)
PCM; electronic–returnless
144)
A(n) ________ is created whenever current travels through a conductor.
144)
A)
Electromagnetic field
B)
Inductive coupling
C)
Electrical discharge
D)
Capacitance coupling
145)
Technician A says that the first number of an OBD II DTC indicates if the code is an industry
standard DTC or a manufacturer specific DTC. Technician B says that the third digit of powertrain
DTCs indicates the specific condition or area (such as engine temperature or engine speed). Which
technician is correct?
145)
A)
Technician A Only
B)
Technician B on ly
C)
Both Technicians A and B
D)
Neither Technician A nor B
146)
Technician A says that pressure regulators are on the downstream (return) side of the injector in
gasoline EFI systems. Technician B says the throttle body injection (TBI) systems require higher
regulated pressures than port injection systems. Which technician is correct?
146)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
147)
Blue exhaust smoke from a turbocharged engine could be caused by any of the following EXCEPT:
147)
A)
A PCV system problem
B)
Coolant leakage into the combustion chambers
C)
Worn rings or valve guides in the engine
D)
A restricted turbocharger oil return line
148)
A dirty air filter is being replaced. Technician A says it could have caused a rich air–fuel mixture.
Technician B says the cover wing nut should be very tight to prevent dirt contamination. Which
technician is correct?
148)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
149)
Technician A says that an engine computer will record only closed–loop faults. Technician B says
that you may have to fix an open–loop fault before identifying a closed–loop fault. Which
technician is correct?
149)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
150)
A fuel line is being replaced. Technician A says steel tubing is the proper replacement. Technician
B says copper tubing may be used. Which technician is correct?
150)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
151)
Technician A says never run a turbocharged engine with the air filter removed. Technician B says
never shut off a turbocharged engine immediately after returning to idle from high–speed
operation. Which technician is correct?
151)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
152)
Which tool would you use to test the ignition control output signal?
152)
A)
DVOM
B)
Scan tool
C)
Test light
D)
Oscilloscope
153)
An OBD II EVAP system that does NOT properly purge the canister can cause:
153)
A)
An incorrect air–fuel ratio
B)
Fuel pressure to increase
C)
Fuel pressure to decrease
D)
The fuel pump to malfunction
154)
There is no vacuum at the oil filler cap in an engine with a PCV system. Technician A says the PCV
system might be clogged. Technician B says there may be too much blowby. Which technician is
correct?
154)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
155)
Technician A says that gasoline fuel injection pressure is in the range of 1000 psi (6900 kPa).
Technician B says that you must relieve fuel system pressure before servicing a gasoline injection
system. Which technician is correct?
155)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
156)
If the engine is cranked while the distributor is out, the ignition must be:
156)
A)
Power timed
B)
Static timed
C)
Advanced
D)
None of the above
157)
Technician A says primary circuit voltage has an indirect effect on secondary circuit voltage.
Technician B says primary circuit voltage loss can not be due to insufficient source voltage from the
battery. Which technician is correct?
157)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
158)
Technician A says that the oxygen sensor heater can be tested with a DVOM by measuring voltage
at the heater. Technician B says that the heater may be tested by using a scan tool and observing
the oxygen sensor voltage over a two minute time period just after the ignition has been turned on.
Which technician is correct?
158)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
159)
A solid–state distributor pickup coil is being tested. One ohmmeter test lead is connected to the
distributor housing and the other lead alternately touched to each pickup coil lead. The ohmmeter
shows infinite resistance. Technician A says the pickup coil is grounded. Technician B says the
pickup coil is not grounded, but it may still be defective. Which technician is correct?
159)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
160)
The idle mixture adjustment on a Bosch K–Jetronic system is often called:
160)
A)
The speed–drop adjustment
B)
An idle balance adjustment
C)
The HC adjustment
D)
The CO adjustment
161)
The PREFERRED way to clear the computer memory on a Ford EEC system is to:
161)
A)
Disconnect the computer memory connector near the battery + terminal
B)
Use the scan tool
C)
Remove the control system fuse from the fuse block
D)
Disconnect a particular connector at the computer
162)
Which of the following could be the cause of excessive NOx emissions?
162)
A)
Excessive rich condition
B)
Vehicle not up to operating temperature
C)
Carbon build–up on pistons
D)
None of the above
163)
A PCV valve is being tested with the engine running. Technician A says the valve should make a
hissing noise. Technician B says vacuum should be felt when placing a finger over the end of the
valve. Which technician is correct?
163)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
164)
An oscilloscope is connected to an injector solenoid. The scope pattern shows a steady, unbroken
trace with the engine creaking. This indicates:
164)
A)
The solenoid has low resistance
B)
The solenoid wiring harness has high resistance
C)
The solenoid has an open circuit
D)
Supply voltage is too high
165)
On most electronic engine control systems, the only adjustable sensor is the:
165)
A)
Manifold absolute pressure (MAP) sensor
B)
Throttle position sensor
C)
Coolant temperature sensor
D)
O2 sensor
166)
Technician A says the OBD II AIR system monitor performs a functional check that tests the ability
of the AIR system to inject fresh air into the exhaust. Technician B says the OBD II functional check
relies on feedback from the catalyst efficiency sensor to determine the presence of airflow. Which
technician is correct?
166)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
167)
Technician A says analog means the voltage signal is either on–off or high–low. Technician B says
digital means the voltage signal is infinitely variable within a given range. Which technician is
correct?
167)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
168)
A vacuum gauge reading fluctuates regularly between five and seven inches on the gauge.
Technician A says a valve spring is broken. Technician B says the valve timing is late. Which
technician is correct?
168)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
169)
When excessive oil enters the combustion chamber, the spark plugs are:
169)
A)
Oil fouled
B)
Ash fouled
C)
Splash fouled
D)
Carbon fouled
170)
The proper method for checking the PCV system is:
170)
A)
With the engine cold, remove the PCV hose from the manifold and check for rpm drop
B)
Bring the engine to normal operating temperature, remove the PCV valve from the engine,
disconnect the valve from the hose, and check for rpm drop
C)
With the engine at normal operating temperature, remove the PCV valve from the engine, do
NOT disconnect the hose from the valve or the manifold, check for strong vacuum with your
thumb placed over the open end of the valve
D)
Remove the PCV valve from the engine, start the engine, check for rpm drop
171)
Technician A says that at the stoichiometric air–fuel ratio of 14.7 to 1, combined O2 and CO2
readings on a 4–gas analyzer should be approximately 14.7%. Technician B says that CO2 should
be high and O2 should be low. Which technician is correct?
171)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
172)
ASM 50/15 type of testing test the vehicle at:
172)
A)
25% load, 15 mph
B)
25% load, 25 mph
C)
50% load, 25 mph
D)
50% load, 15 mph
173)
High O2 and low CO levels can be caused by:
173)
A)
Defective injector
B)
Lean mixture
C)
O2 sensor
D)
Any of the above
174)
One common cause of high fuel pressure is ________.
174)
A)
Stuck open fuel injectors
B)
A restricted fuel supply line
C)
Inoperative fuel injectors
D)
A defective fuel pressure regulator
175)
Soft, black, sooty deposits on a spark plug indicate:
175)
A)
Normal wear
B)
Ash fouling
C)
Carbon fouling
D)
Splash fouling
176)
Technician A says an engine tune–up can lower the emission levels on an older vehicle. Technician
B says new filters and plugs can improve emission levels by increasing fuel delivery, air intake and
combustion efficiency. Which technician is correct?
176)
A)
Technician A only
B)
Technician B only
C)
Both Technicians A and B
D)
Neither Technician A nor B
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
177)
The majority of switched outputs are ________ drivers.
177)
178)
Analog manifold absolute sensors produce a ________ voltage when the manifold vacuum
is low and a ________ voltage when the manifold vacuum is high.
178)
179)
Constant volume sampling equipment used for the Federal Test Procedure (FTP) measures
emissions in ________.
179)
180)
Vehicles must be ________ before performing an emission test.
180)
181)
Zirconia type oxygen sensors produce a ________ voltage when the air–fuel mixture is lean
and a ________ voltage when the fuel mixture is rich.
181)
182)
A properly operating oxygen sensor should transition from rich to lean approximately
________ times per second.
182)
183)
Most relays that are PCM controlled are controlled by the PCm switching the ________ side
of the relay ________.
183)
184)
Most Mass air flow sensors produce a ________ signal.
184)
185)
Analog inputs are inputs where the voltage is ________ variable.
185)
186)
Two–speed tailpipe tests usually test the exhaust gas concentrations at ________ and
________.
186)
187)
ASM 50/15 or similar tests involve testing the exhaust emissions while the vehicle is
operated on a ________.
187)
188)
High COs always indicate an excessive ________ condition.
188)
189)
Ford manifold absolute sensors produce a(n) ________ signal.
189)
TRUE/FALSE. Write ‘T’ if the statement is true and ‘F’ if the statement is false.
190)
An exhaust gas oxygen (O2) sensor can be tested for resistance using an ohmmeter.
190)
191)
A vacuum leak test can show worn intake valve guides.
191)
192)
Silicone grease used on some distributor rotors suppresses radio frequency interference (RFI).
192)
193)
If you are using a scan tool to command a relay on and the scan tool indicates that the relay is
commanded on then the relay must be good.
193)
194)
The primary circuits of all electronic ignitions are grounded through the ignition module.
194)
195)
Vacuum readings drop as altitude increases.
195)
196)
When installing a 0.55–inch (14–mm) tapered–seat spark plug, you should torque it to 30 ft–lbs. (41
NM).
196)
197)
On an OBD II equipped vehicle when the MIL is illuminated it means a code has set and the fault is
present.
197)
198)
The numbers on Ford’s bi–level Dura–Spark I distributor cap indicate firing order.
198)
199)
V–type engine intake manifold removal is simpler than inline engine manifold removal.
199)
200)
When replacing a fuel tank, the filler cap should be removed before any fuel lines are disconnected.
200)
201)
All infrared analyzers should be calibrated regularly.
201)
202)
A steel feeler gauge is used to check the air gap between the trigger wheel and the pickup coil and
magnet in some distributors.
202)
203)
A spark plug cable with a loose spark plug terminal can be caused by improper handling of the
plug cables.
203)
204)
An incorrectly installed fuel filter will restrict fuel flow.
204)
205)
Vacuum diagrams are often color codes.
205)
206)
A coolant–temperature trouble code means a bad coolant–temperature sensor.
206)
207)
Engine vacuum tests should be made at low engine operating temperatures.
207)
208)
The usual replacement interval for fuel filters is 20,000 miles.
208)
209)
Air cleaner sensor specifications are generally the same.
209)
210)
Penetrating oil can be used with a vacuum gauge to verify sticking valves.
210)
211)
Oil can be squirted into horizontal engines to check for bad rings or valves.
211)
212)
Most throttle actuators can manually be positioned by hand.
212)
213)
A clogged PCV system can cause lean operation at idle.
213)
214)
Before servicing an electronic ignition system, the TACH terminal should be grounded.
214)
215)
Pickup coil resistance in a magnetic–pulse distributor is checked using a voltmeter connected
across the pickup coil connector terminals.
215)
216)
A loose, corroded, or otherwise bad coil high–voltage lead can cause an engine to misfire on several
cylinders at random.
216)
217)
The PCV valve is usually located in the ported vacuum hose to the carburetor.
217)
218)
The positive battery terminal must be disconnected before work on any fuel system component
begins.
218)
219)
Vacuum leaks at the throttle body are indicated by an above normal vacuum reading.
219)
220)
Normal HC and high CO analyzer readings at idle may be caused by a dirty air filter.
220)
221)
Dwell may be measured with an oscilloscope.
221)
222)
When performing an OBD II I/M test if there are any stored trouble codes the vehicle will fail.
222)
223)
Normal HC and high CO analyzer readings at 2500 rpm may be caused by a dirty air filter.
223)
224)
All gases that are measured by the gas analyzer are measured in parts per million (PPM).
224)
225)
Fuel pump delivery volume is measured at idle and 2000 rpm.
225)
226)
Special testers are available for Ford EEC systems.
226)
227)
All fuel line tubing ends should be double flared.
227)
228)
Some Ford and Cadillac engines use a screw–on, replaceable fuel filter.
228)
229)
On a non OBD II equipped vehicle if a hard code is set it usually indicates that the fault exists at
that time.
229)
230)
Infrared analyzers are affected by altitude.
230)
231)
A compression gauge measures how well a cylinder holds compression pressure.
231)
232)
You can install a cold spark plug to cure an engine overheating problem.
232)
233)
High HC and low CO analyzer readings at idle may be caused by spark plug misfire.
233)
234)
To test engine performance, a vacuum gauge must be connected to ported vacuum.
234)
235)
A carbon track on the distributor rotor can cause an engine to misfire on several cylinders at
random.
235)
236)
In a vacuum test of the PCV system, the gauge reading should increase when the PCV hose is
pinched.
236)
237)
A mechanical condition inside the cylinder can affect secondary resistance.
237)
238)
Secondary oscilloscope patterns indicate the resistance of spark plugs, cables, and other secondary
circuit parts.
238)
239)
You can use a colder spark plug in an engine used for high–speed operation than you can in an
engine used only for stop–and–go driving.
239)
240)
A coolant–temperature trouble code can indicate either a high–temperature or a low–temperature
fault.
240)
241)
Retrofit PCV devices are installed on late–model engines.
241)
242)
Most relays that are PCM controlled are pulse width modulated.
242)
243)
An air–fuel ratio exhaust analyzer is graduated to read in parts per million (ppm).
243)
244)
Before servicing an electronic ignition system, it is necessary to disconnect and ground the battery
voltage, or BAT connector.
244)
245)
If the tachometer reading drops by 40 to 80 rpm during an engine speed drop test, the PCV system
is clogged.
245)
246)
High–side drivers apply a voltage to the output device.
246)
247)
Most U.S.–built cars have an externally vented fuel tank.
247)
248)
Flexible fuel hoses are used at the ends of steel fuel lines to absorb vibration.
248)
249)
Output drivers that are fault protected can turn themselves off when excessive current flow is
sensed.
249)
250)
Fuel hoses that feel soft may be deteriorating.
250)
251)
You should do an overall system performance test as the first step of troubleshooting an electronic
engine control problem.
251)
252)
A dirty PCV filter in the air cleaner must be replaced.
252)
253)
To test dwekk at a specific engine speed, it is necessary to double the distributor rpm.
253)
254)
A computer PROM should be removed and installed with the ignition switch ON.
254)
255)
You must remove any silicone grease to prevent high–voltage arcing inside the distributor.
255)
256)
High HC and normal CO analyzer readings at idle may be caused by a lean air–fuel mixture.
256)
257)
All scan tools have bi–directional capability.
257)
258)
High HCs can be caused by excessively rich or an excessively lean condition.
258)
259)
Most diagnostic flow charts are designed to account for intermittent problems.
259)
260)
Thermostatically controlled air cleaner problems can cause erratic cold–engine performance.
260)
261)
The three oscilloscope patterns are superimposed, parade, and raster.
261)
262)
Pulse width modulation is a method of controlling an output by varying the amount of on and off
time of a digital signal to an output.
262)
263)
Pressure and volume tests are not done on electric fuel pumps.
263)
264)
Recommended replacement intervals for EEC filters range from 50,000 to 75,000 miles.
264)
265)
The HC hang up check is designed to detect the presence of excessive HCs in the air surrounding
the emission analyzer.
265)
266)
The more dwell variation an engine has, the better.
266)
267)
High coil voltage can cause a terminal to separate from a spark plug cable.
267)
Answer Key
Testname: FULL
Answer Key
Testname: FULL
Answer Key
Testname: FULL
Answer Key
Testname: FULL
Answer Key
Testname: FULL
Answer Key
Testname: FULL