Oxygen Sensor Replacement

[bmangan]

Hi,

I have a 2003 Saturn Vue. I currently have the following OBDII codes that will prevent my vehicle from passing inspection.

P0031, P0031, P0134, P0135

All of these codes seem to be related to the Front Bank 1 Oxygen Sensor. My belief is that simply replacing the offending sensor would fix my current issues. Does anyone know if the codes indicate a more significant problem?

There are two O2 sensors on the engine block. One for the three cylinders on the front of the engine and one for the three cyclinders on the back of the engine. The O2 sensor for the front is very easy to access, the one on the back does not appear to be readily accessible. Is the Front Bank One sensor the one on the front of the engine?

Finally, I have located a replacement sensor without the wiring harness for around $50. The replacement sensor with the harness from the Saturn dealer is priced at $116. That seems like an awful high price to pay for the wiring harness. Has anyone had problems or issues when just replacing the sensor and using the existing wiring harness?

Thanks in advance for any advice on my problem.

Brendan

[body-snatch-her]

Well, something to consider is that the fault could be from a bad harness while the existing sensor could still be good! (One way to determine that would be to swap the stuff around and see how the codes change.)
To answer your specific question though, there should be no need to change the harness when you change the sensor as long as the connectors match, make good contact, and the wiring is in good shape. Replacing the wiring could be a good preventative approach though.