ASE A8 Engine Performance Practice Test

46. Technician A says to complete the recommended drive cycle after replacing the vehicle’s engine control module. Technician B says completing a drive cycle includes steps like driving the vehicle at certain speeds for a set period of time. Who is correct?

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

46.

Answer A is wrong. Complete a drive cycle to set OBD II monitors. It includes steps like accelerating, cruising, and decelerating the vehicle at certain speeds for a set period of time.

Answer B is wrong. Disconnecting power from the engine control module renders OBD II monitors not ready to monitor vehicle emissions.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Both technicians are correct.

47. A vehicle has a momentary hesitation only during acceleration. The MOST likely cause of this condition is:

  • A. A faulty exhaust gas recirculating valve. (EGR)
  • B. A faulty oxygen sensor. (O2) sensor
  • C. A faulty positive crankcase ventilation valve. (PCV)
  • D. A faulty throttle position sensor. (TPI)

47.

Answer A is wrong. This actuator would not likely cause this condition.

Answer B is wrong. This sensor would not likely cause this condition.

Answer C is wrong. This valve would not likely cause this condition.

Answer D is correct. A faulty TP sensor would cause this condition.

48. A four cylinder EFI engine has an engine code indicating insufficient EGR flow. The EGR solenoid has been tested and found to be faulty. This faulty solenoid will result in which of these conditions.

  • A. High CO emissions.
  • B. High HC emissions.
  • C. High CO2 emissions.
  • D. High NOx emissions.

48.

Answer A is wrong. CO stands for carbon monoxide. Carbon monoxide is the toxic compound that forms with partially burned fuel from rich fuel mixtures.

Answer B is wrong. HC stands for hydrocarbon. Hydrocarbons are unburned fuel resulting from rich fuel mixtures and misfires.

Answer C is wrong. CO2 stands for carbon dioxide. Carbon dioxide is actually desired over carbon monoxide, though it is considered a greenhouse gas.

Answer D is correct. NOx stands for oxides of nitrogen. The x is a variable. These gases are formed with high cylinder temperatures. They are considered pollutants. A stuck open EGR valve will result in excessive exhaust gas flow into the intake manifold. This results in engine stumble at idle. A stuck closed EGR valve will result in excessive NOx emissions.

49. A vehicle has suffered a sudden drop in fuel economy. The variable valve solenoid is commanded on and there is no change in engine operation. Technician A says to inspect the variable valve system’s oil control valve. Technician B says contaminated engine oil can result in this condition. Who is correct?

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

49.

Answer A is wrong. VVT or variable valve timing adjusts valve timing to meet operating conditions. The easiest and most common method advances and retards valve timing, but does not alter valve lift. Newer more efficient systems also alter valve lift and duration.

Answer B is wrong. Regular maintenance and oil changes are vital. The actuators and phasers in these systems are operated by oil pressure.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Both technicians are correct.

50. Technician A says a (TPI) throttle position sensor is a potentiometer that indicates throttle angle. Technician B says a throttle position sensor can be tested for resistance with an ohmmeter. Who is correct?

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

50.

Answer A is wrong. The TPI, TPS or throttle position sensor is a potentiometer that varies voltage signals to the PCM according to throttle angle. Both technicians are correct.

Answer B is wrong. This sensor is best tested with a scanner, but can be tested for proper resistance and sweep with a ohmmeter.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Both technicians are correct.

ASE A8 Engine Performance Quiz
Scored (out of 100%)