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Quiz Session - Attempts With Random Questions

ASE L1 Exam Questions

Page 6 of 10

101.

All the following can cause a hard starting condition EXCEPT:

  • Bad fuel pump relay

  • A faulty camshaft position sensor

  • A weak fuel pump

  • Fouled spark plug

Correct answer: Bad fuel pump relay

A bad fuel pump relay would prevent the engine from starting and cause a no-start condition. All the other options could result in hard starting.

102.

Technician A says variable valve timing (VVT) actuators run by the ECM increase valve lift and duration with an increase in engine speed. Technician B says many VVT actuators use engine oil for hydraulic operation. 

Who is correct?

  • Both A and B

  • Technician A

  • Technician B

  • Neither A nor B

Correct answer: Both A and B

Both technicians are correct. When the VVT actuators are run by the ECM, valve lift and duration increase with engine speed.

Actuators often use engine oil for hydraulic operation, but some use motors instead. 

103.

Technician A says overly advanced timing will increase HC levels. Technician B says retarded timing will decrease HC levels. 

Who is correct?

  • Both A and B

  • Technician A

  • Technician B

  • Neither A nor B

Correct answer: Both A and B

Both technicians are correct. Timing has a noticeable effect on HC emissions levels. HC will increase with advanced timing and decrease with retarded timing. Very retarded timing causes an increase in HC. 

104.

Which pin on an OBD II 16-pin connector supplies ground to a connected scan tool?

  • 4

  • 6

  • 10

  • 16

Correct answer: 4

Early on, manufacturers were free to use their own on-board diagnostics OBD connector design. The introduction of OBD II in 1996 brought about a standardized 16-pin design. Pin 16 is B+ (power), and pin 4 is ground. This eliminates the need for a separate power source when connecting a scan tool. 

105.

Technicians are discussing the composite vehicle. Technician A says the manifold absolute pressure is 70.8 kPA when the voltage reads 3.00. Technician B says manifold absolute pressure sensor output should read 4.50 volts at KOEO (key on engine off) at sea level. 

Who is correct?

  • Both A and B

  • Technician A

  • Technician B

  • Neither A nor B

Correct answer: Both A and B

Both technicians are correct. According to the MAP sensor for the composite vehicle, a voltage reading of 3.00 would indicate a manifold absolute pressure of 70.8 kPA

At sea level, the sensor output should be 4.50 volts with KOEO. 

106.

The composite vehicle is being discussed. Technician A says high resistance at TCM terminal 337 could affect TCC operation. Technician B says an opening at TCM terminal 310 could affect TCC operation. 

Who is correct?

  • Technicians A and B

  • Technician B

  • Technician A

  • Neither A nor B

Correct answer: Technicians A and B

Both technicians are correct. High resistance at transmission control module (TCM) terminal 337 could cause problems with the vehicle speed sensor (VSS) input to the TCM. The VSS signal is one of the main inputs to the TCM for torque converter clutch (TCC) control. 

Technician B is correct because an opening at TCM terminal 310 would affect shift solenoid D performance, which would put the transmission into fail-safe mode. In fail-safe mode, the TCC is disabled.

107.

If the first numerical digit of a DTC is one, what is true about the code?

  • It is an OEM code

  • It is a generic code 

  • It is a powertrain code 

  • It is a vehicle system code 

Correct answer: It is an OEM code

The first numerical digit of a DTC indicates whether the code is OEM or generic. If the code is generic, this digit will be a zero. If the code is OEM, this digit will be a one. 

Vehicle area codes are specified by the first letter in the DTC. B indicates Body, C indicates Chassis, P indicates Powertrain, and U indicates Network. The vehicle system codes are found in the second numerical digit of the DTC. 

108.

During the ASM 5015 test, the dynamometer applies a load that is what percentage of the FTP standard? 

  • 50%

  • 15%

  • 25% 

  • 75%

Correct answer: 50%

During the 5015 portion of the Acceleration Simulation Mode (ASM) emissions test, the load applied to the vehicle is 50% of the Federal Test Procedure (FTP) standard. 

109.

Which of the following represents a rich air/fuel mixture?

  • 13:1

  • 14.7:1

  • 15:1

  • 16:1

Correct answer: 13:1

An air/fuel ratio of 14.7:1 is the optimum ratio for a gasoline engine. Anything less than 14.7 is rich, and anything greater than this is lean. 

110.

Technician A says OBD I systems have a malfunction indicator light (MIL) that goes out after the problem disappears. Technician B says the MIL in OBD II systems remains on until the vehicle runs three consecutive trips without a repeated failure. 

Who is correct?

  • Both A and B

  • Technician B

  • Technician A

  • Neither A nor B

Correct answer: Both A and B

Both technicians are correct. With the OBD I system, the MIL only remains on while the fault is current. If the problem is resolved, the MIL disappears.

With an OBD II system, the vehicle must run three consecutive trips without the fault reoccurring for the light to turn off on its own. 

111.

Technician A says "direct ignition" is a term for ignition systems that use a distributor. Technician B says direct ignition systems are designed to minimize secondary resistance. 

Who is correct?

  • Technician B

  • Technician A

  • Both A and B

  • Neither A nor B

Correct answer: Technician B

Technician B is correct. Direct ignition systems are designed to minimize secondary resistance by eliminating the plug wires.

Technician A is incorrect. The term "direct ignition" is used to describe ignition systems that use individual coils for each cylinder. 

112.

What is the maximum allowable voltage drop across a computer ground?

  • 0.10 volts

  • 0.30 volts

  • 0.20 volts

  • 0.40 volts

Correct answer: 0.10 volts

With the engine running, the maximum allowable voltage drop across a computer ground is 0.10 volts. If the voltage is higher, high resistance is indicated. 

113.

The FT sensor on the composite vehicle reads 2.6 volts. This indicates what fuel temperature?

  • 86 degrees Fahrenheit

  • 104 degrees Fahrenheit

  • 68 degrees Fahrenheit

  • 32 degrees Fahrenheit

Correct answer: 86 degrees Fahrenheit

The fuel temperature (FT) sensor on the composite vehicle is a negative coefficient sensor, so resistance decreases as the temperature goes up. Looking at the temperature-versus-voltage chart, a voltage reading of 2.60 indicates a temperature of 86 degrees Fahrenheit.

A temperature of 104 degrees Fahrenheit would provide a reading of 2.27 volts, while 68 degrees Fahrenheit would correlate to 2.93 volts. A temperature of 32 degrees Fahrenheit reflects a reading of 3.59 volts. 

114.

Clear flood mode on the composite vehicle is initiated by the PCM during cranking when what happens? 

  • The accelerator pedal is depressed 80% or greater with engine speed below 400 rpm

  • The accelerator pedal is depressed 60% or greater with engine speed below 500 rpm

  • The accelerator pedal is depressed 75% or greater with engine speed below 300 rpm

  • The accelerator pedal is depressed 90% or greater with engine speed below 600 rpm

Correct answer: The accelerator pedal is depressed 80% or greater with engine speed below 400 rpm

In the composite vehicle, the powertrain control module (PCM) will force the engine control system to enter "clear flood" mode when the accelerator pedal is depressed 80% or greater and the engine speed is below 400 rpm. This is done to prevent flooding. 

With the clear flood mode activated, the ECM shuts off the fuel injectors. 

115.

Technician A says a restricted exhaust causes combustion gases to exit through an open intake valve. Technician B says a restricted exhaust causes manifold vacuum to rise significantly. 

Who is correct?

  • Technician A

  • Technician B

  • Neither A nor B

  • Both A and B

Correct answer: Technician A

Only technician A is correct. With a restricted exhaust, the combustion gases get trapped in the cylinder before exiting the path of least resistance, which is through the open intake valve instead of the exhaust valve.

Technician B is wrong because a restricted exhaust is going to lead to a significant manifold vacuum drop. 

116.

Technician A says the EGR valve raises manifold pressure. Technician B says the EGR valve raises the vacuum. 

Who is correct?

  • Technician A

  • Technician B

  • Both A and B

  • Neither A nor B

Correct answer: Technician A

Only technician A is correct. The EGR valve raises manifold pressure but lowers the vacuum. Therefore, a leaking EGR valve causes a low and steady vacuum reading with a closed throttle. 

117.

What is the cause of a resistance reading of 120 ohms between pin 6 and pin 14 on the OBD II diagnostic connector? 

  • One missing or open terminating resistor

  • Normal operation

  • Short to ground

  • Bad diagnostic connector terminal

Correct answer: One missing or open terminating resistor

In terms of the resistance between pins 6 and 14 on the OBD II diagnostic connector, a value of 120 ohms indicates either a missing or open terminating resistor.

Normal operation shows a resistance of 60 ohms.

118.

To check for a restricted exhaust system, the first vacuum reading should be taken with the car running at what rpm?

  • 1000

  • 2500

  • 1500

  • 2000

Correct answer: 1000

To check for a restricted exhaust system, the vacuum gauge is first read at 1000 rpm with the engine at normal operating temperature. Once that reading is recorded, engine speed should be slowly increased to 2500 rpm.

If the reading drops more than 3 in. Hg from the initial value, the exhaust system may be restricted. 

119.

Which type of crank sensor produces an AC voltage signal? 

  • Permanent magnet 

  • Hall-effect 

  • Reed switch

  • Photo-optical 

Correct answer: Permanent magnet

A permanent magnet crankshaft sensor produces its own AC voltage when a reluctor wheel passes by. The AC voltage created is in direct relation to the engine speed.

The other types of sensors all produce a DC voltage signal. 

120.

Which of the following is MOST likely to cause spark knock?

  • EGR valve stuck closed 

  • EGR valve stuck wide open

  • EGR valve not seating

  • Excessive backpressure on a positive-backpressure EGR valve

Correct answer: EGR valve stuck closed

An exhaust gas recirculation (EGR) valve that is stuck closed will increase combustion temperature, possibly resulting in a spark knock. Clogged passages can also lead to a spark knock.

When an EGR valve is stuck wide open, the result is a no-start condition, while an EGR valve that isn't seated causes a rough idle. When there's excessive backpressure (positive backpressure valves only) or improper vacuum control, there may be some engine hesitation. 

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