1) Another name for an exhaust gas oxygen sensor (O2S) in European vehicles is:
A. alpha sensor
B. beta sensor
C. lambda sensor
D. sigma sensor

2) The oxygen sensor signal is based on the amount of oxygen in the ________ gas.
A. pressurized
B. exhaust
C. recirculating
D. heated

3) Zirconia oxygen sensors produce a _________ based on the amount of oxygen in the exhaust.
A. resistance
B. wattage
C. current
D. voltage

4) O2 sensors will trigger a diagnostic trouble code (DTC) on OBD II compliant vehicles, turning on the Malfunction Indicator Lamp (MIL) when tailpipe emissions exceed federal limits by:
A. 1.5 times
B. 2.5 times
C. 5 times
D. 10 times

5) When the fuel mixture is lean, it means that there is more _________ in the exhaust stream.
A. fuel
B. oxygen
C. carbon
D. emissions

6)  When diagnosing O2 sensor problems, check the sensor’s heater ground. A poor ground adds ________ to the circuit which prevents the heater heating the sensor sufficiently and may cause inaccurate sensor operation.
A. voltage
B. resistance
C. current
D. calibration

7) The signal from Zirconia O2 sensors varies between _________.
A. -5 and 0.5 volts
B. 0 and 1 volt
C. 5 and 6 volts
D. 10 and 20 volts

8) Which of these is NOT a type of O2 sensor used in automotive vehicles?
A. zirconia
B. titania
C. iridium
D. heated planar
E. wide-band

9) An oxygen sensor must be hot – ____________ – before it will generate valid  voltage signals that can be used to maintain closed loop fuel control.
A. about 250° F
B. about 500° F
C.  about 650° F
D. about 850° F

10) As an O2 sensor ____________, it can cause excessive gasoline consumption and elevated emissions.
A. improves
B. operates
C. develops
D. deteriorates

Scroll down for Answers

The following are the answers to the T2 Pop Quiz on Oxygen Sensors from the May, 2008 issue.

1)  C. lambda sensor

2)  B. exhaust

3)  D. voltage

4)   A. 1.5 times

5)   B. oxygen

6)   B. resistance

7)   B. 0 and 1 volt

8)  C. iridium

9)  C.  about 650° F

10)  D. deteriorates