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Eric, Automotive Repair Shop Manager
Category: Saturn
Satisfied Customers: 32049
Experience:  20+ yrs. experience as repair shop manager and technician.
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Saturn VUE: I need to replace O2 sensors on my 2003 Saturn

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I need to replace O2 sensors on my 2003 Saturn VUE 2.2 4-cyl. The diagnose system says I need to replace both O2 sensors (Bank 1 sensor 1 and Bank 1 sensor 2). I do not want to buy expensive sensors (like Bosch) because I will sell the car in a month. So I am about to buy Denso replacement sensors parts number(NNN) NNN-NNNN(upstream) and number(NNN) NNN-NNNN(downstream). If my plan sounds good, can you guide me through the replacement process showing where these sensors are located, what tools I will need, and how to make a proper job. Thanks.

Good choice on the sensor brand. Denso is actually a better O2 sensor than the Bosch.

You will need an O2 socket and a ratchet




Customer: replied 4 years ago.

Hi Eric,

Thanks for your reply. I am not sure what the "liquid penetrate" and the "anti-seize" compound actually are. Would I need to buy these two things as well? Also, you say I will need a O2 socket, but in the installation procedure this socket is not mentioned. At what stage will I need to use it and in which way?




the new O2 sensors should come with the anti seize compound. the liquid penetrate is like PB Blast or WD40 or Liquid Wrench. Spray it on the old O2 sensor to make it easier to remove.

The O2 sensor socket is what they refer to as an O2 sensor wrench.

It is a socket with a slot in the side for the wiring to go thru

you use it to loosen the old O2 sensor and tighten the new one.
Customer: replied 4 years ago.

Hi, Thanks again for your reply. Just a couple last questions. How do I turn off the light "Service engine soon" after the replacement? Should I reset something? Also, do you have any further advice for doing a good job?

I will rate you 5 stars when I read your answer.

Thanks a lot.



there are 3 ways to turn the light off.

1 - with code reader/scan tool. unless you live in California, you can run it by any major parts store such as Autozone and they will do this for free

2 - 50 drive cycles(at least 10 miles per) without computer detecting the same fault and the light turns off on its own

3 - disconnect both battery cables and tape/clamp the battery cable ends together for 10 minutes. this discharges the capacitors in the computer and erases the fault codes.
This is the one I recommend the very least for several reasons - it will lock the radio and if you dont have your unlock code, you will have to pay a dealer to unlock it, it will usually set the antitheft system and can require it to be towed to dealer to have reprogrammed, and it can cause it to run rough and shift rough until the computer relearns the parameters.

the sensors are fairly straightforward to replace. About the only thing to make it easier is to spray them with PB Blast or WD40 and let it soak for an hour. The sensor threads become heat seized over time, so this is best way to free them so you dont fight them for a couple of hours trying to loosen them

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