2.   Technician A says the heater circuit in an
oxygen senser is meant to bring this senser to
operating temperature sooner. Technician B
says the oxygen senser senses the oxygen in
the exhaust when it is in closed loop. Who is
correct?

    A. Technician A

    B. Technician B

    C. Both Technician A and B

    D. Neither Technician A or B
3.   Technician A says a stuck closed EGR valve
will cause an engine to stumble or stall.
Technician B says a open EGR valve will cause
an engine to ping.  Who is correct?


    A. Technician A

    B. Technician B

    C. Both Technician A and B

    D. Neither Technician A or B
4.   Technician A says the Manifold Absolute
Pressure senser senses pressure in the intake
manifold.Technician B says the Mass Air Flow
Sensor senses air volume in the air tube to
indicate engine load.  Who is correct?

    A. Technician A

    B. Technician B

    C. Both Technician A and B

    D. Neither Technician A or B
5.   Technician A says an Air / Fuel Sensor is
designed to reach and keep a vehicle at
Stoichiometry. Technician B says Stoichiometry
is 15.7:1 air to fuel mixture. Who is correct?

    A. Technician A

    B. Technician B

    C. Both Technician A and B

    D. Neither Technician A or B
6.   Technician A says a stuck open PCV valve will
cause a lean 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
7.   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
8.   Technician A says that the Evaporative Purge
Valve releases fuel vapor to the intake manifold
instead of the atmosphere. 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
9.   There is black smoke coming from the tailpipe
of a vehicle. The most likely to cause this condition
is:

    A. A rich fuel condition.

    B. Worn piston rings.

    C. A blown head gasket.

    D. Leaking valve seals.
10.   An oxygen sensor has a voltage reading of .20
volts. Technician A says this indicates a rich fuel
mixture. Technician B says .45 is 14.7:1 or
Stoichiometry.  Who is correct?

    A. Technician A

    B. Technician B

    C. Both Technician A and B

    D. Neither Technician A or B
Free A.S.E. Study Guide
     An ASE Study Guide for the Automotive Technician
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1.   Which is the least likely to cause a vehicle to
have a rich fuel condition:

    A. Leaking Fuel Injector

    B. Fuel Pressure Regulator

    C. Engine Coolant Temperature Sensor

    D. Stuck Closed Thermostat
A-8 Engine Performance
Sample Test