11.  Which of these is least-likely to cause a rich fuel condition:

A A leaking fuel injector.

B A faulty fuel pressure regulator.

C A faulty ECT engine coolant temperature sensor.

D A stuck closed thermostat.

16.   Technician A says a stuck open PCV valve will cause a lean fuel condition. Technician B says the PCV system removes blowby gases from the crankcase. Who is correct?

A Technician A

B Technician B

C Both Technician A and B

D Neither Technician A or B

12.   Technician A says the heater circuit in an oxygen sensor is designed to bring the sensor to operating temperature sooner. Technician B says the engine control module uses the oxygen sensors voltage signal to adjust fuel trim in closed loop. Who is correct?

A Technician A

B Technician B

C Both Technician A and B

D Neither Technician A or B

17.   Technician A says the crankshaft position sensor monitors the crankshafts speed and rotation. Technician B says a permanent magnet sensor has three wires. Who is correct?

A Technician A

B Technician B

C Both Technician A and B

D Neither Technician A or B

13.   Two technicians are discussing a turbocharged engine. Technician A says the wastegate is a component used to control boost pressure. Technician B says when opened the wastegate diverts exhaust gas from the turbine wheel. Who is correct?

A Technician A

B Technician B

C Both Technician A and B

D Neither Technician A or B

18.   Technician A says a defective evaporative purge valve may cause a rich air fuel ratio. Technician B says an evaporative pressure sensor is used to notify the PCM of gas tank pressure. Who is correct?

A Technician A

B Technician B

C Both Technician A and B

D Neither Technician A or B

14.   An emission test on a six cylinder engine indicates high levels of NOx. The most likely cause of this condition is:

A A rich air fuel mixture.

B A clogged catalytic converter.

C A cylinder misfire.

D A stuck closed EGR valve.

19.   A cylinder power balance test is being performed on a four cylinder engine. A spark plug wire is removed from its corresponding spark plug and a slight drop in RPM is noticed.

A This is normal.

B A significant drop should be indicated.

C There should be no drop at all.

D There is no such thing as an engine cylinder power balance test.

15.   

Technician A says to perform a voltage drop test if a corroded ground connection is suspected. Technician B says to perform a voltage drop test if excessive resistance in the circuit is suspected. Who is correct?

A Technician A

B Technician B

C Both Technician A and B

D Neither Technician A or B

20.  

 A cylinder compression test is performed on an eight cylinder engine. These results most likely indicate:

A Burned exhaust valves.

B Weak piston rings.

C A faulty head gasket.

D Retarded valve timing.