ASE A1 Engine Repair Practice Test

1. An engine gradually overheats at cruising speeds but returns to normal at idle. Both of the engine's electric cooling fans are functioning correctly. Which of the following is MOST likely causing this condition?

  • A. A restriction in the radiator.
  • B. A stuck closed fan relay.
  • C. A faulty radiator cap.
  • D. A leak in the cooling system.

1.

Answer A is correct. An internal restriction in the radiator alters the flow of coolant, causing the engine to overheat. Inspect the radiator for external damage and use an infrared thermometer to find internal restrictions.

Answer B is wrong. If the fan relay is stuck closed, the fan motor will operate continuously.

Answer C is wrong. A problem with the radiator cap would also affect the engine's operating temperature at idle.

Answer D is wrong. A leak in the cooling system results in engine overheating at all speeds.

2. A technician is checking for piston ring groove clearance. The proper technique includes:

  • A. The old ring and a feeler gauge.
  • B. The new ring and a feeler gauge.
  • C. Only a feeler gauge.
  • D. No feeler gauge is required.

2.

Answer A is wrong. Technician B is correct.

Answer B is correct. Clean the pistons in a cold tank and then clean the grooves with a ring groove cleaner before measuring.

Answer C is wrong. Technician B is correct.

Answer D is wrong. Technician B is correct.

3. A cylinder power balance test is being performed on a vehicle with sequential fuel injection. The number five cylinder's rpm drop is less than all of the others. Technician A says this could be the result of a restriction in the fuel injector. Technician B says this could be caused by leaking secondary insulation. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

3.

Answer A is wrong. Both technicians are correct.

Answer B is wrong. Both technicians are correct.

Answer C is correct. Both restricted fuel injectors and leaking secondary wires will reduce the cylinder's contribution. Anything that would have an affect on the cylinder's power. It could be mechanical like a faulty valve, possibly the ignition, or the fuel mixture affecting this cylinder's power output.

Answer D is wrong. Both technicians are correct.

4. A turbocharger wastegate is sticking. Technician A says a stuck open wastegate will result in overboost. Technician B says a stuck closed wastegate will result in an underboost condition. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

4.

Answer A is wrong. Neither technician is correct. It’s backwards, a stuck open wastegate (P0299) results in poor performance and a lack of horsepower because the exhaust pressure is bypassing the turbine wheel.

Answer B is wrong. A stuck closed wastegate produces overboost. Overboost results in detonation from the excessive cylinder pressure.

Answer C is wrong. Neither technician is correct.

Answer D is correct. Neither technician is correct.

5. Technician A says that insufficient hydraulic lifter preload results in excessive valve train noise. Technician B says excessive hydraulic lifter preload results in a high intake manifold vacuum. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

5.

Answer A is correct. Insufficient lifter preload will cause valve train noise.

Answer B is wrong. Excessive hydraulic lifter preload causes a low intake manifold vacuum.

Answer C is wrong. With a hydraulic lifter, first set the gap to zero lash, and then set the preload.

Answer D is wrong. This initial zero lash adjustment prevents valve tap and is why hydraulic lifters have a quieter operation.