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Discussion Starter #1
Cant find anything on 02 sensors... How to insatll them how to find them stuff like that.. [wrenchin] I have a code on one and i want to replce it but i cant find anything that shows me where thay are. So if any one has a link to the positions of them it would be helpful..
 

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Mine has thrown a O2 slow to respond code several times after clearing it with a scanner it stays away for several months. Be sure to check the code and see if it's just a blip or if it continues as a failed O2 sensor.
 

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If you follow your exhaust you'll find them. There is a pre cat sensor that is right before the cat. You can see this one if you look under your car. The post cat sensor you'll have to jack it up and really get under there. You might need a O2 sensor tool to get them off. I've done it with wrenches though. Just depends. Do you know the exact code. It'll tell you which one. Also, if you get a new sensor and it's Bosch, I've heard the svtf don't like those to much. Might want to get oem.
 

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They are easy to change out.

disconnect plug to O2 sensor
unscrew sensore (using crescent wrench or o2 sensor tool)
screw new one in tightening it with one of these tools ^^^
plug connector back in and you're on your way
 

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> I installed it and im getting the 141 still and the 136 code errrrrrr...

Did you reset the codes after changing it? If you do not reset them, it may take a while for them to reset by themselves.


You can also check the connectors for corrosion and the wires for damage as that could also give the codes.
 

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ya it was a 141 code the rear one... and ya autozone gave me the bosh one..
I couldn't get the bosch post-cat in. It was too tall and would hit the half shaft. Also had problems getting a bosch pre-cat one in as well. Hit the trans case. Interesting.

Tnealey, have you checked for an exhaust leak?
 

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Discussion Starter #11
The bosch 02 sensor went in easy.. And no i havent looked for a exhaust leak but wouldnt that make my car sound deffrent? i just found it strange that i only had a 141 code now i have both with a new sensor..
 

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> i just found it strange that i only had a 141 code now i have both

Going from the one code to those two codes would suggest a connection/wiring problem, or the wrong sensor.

P.S. The Rock Auto catalog says the correct O2 sensor is Bosch part number 15717. Is that the one they sold you?
 

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Discussion Starter #14
no thats not the one, thay gave me 15718<<< witch goes befor the catalytic converter there web site says, so looks like thay gave me the wronge one..... so i will have to change it out and see if that works thanks ... now let me ask, is it good to do both at the same time, or is it no big deal?
 

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> looks like thay gave me the wronge one.....

That may explain a lot.

> is it good to do both at the same time, or is it no big deal?


The upstream and downstream serve different purposes. The upstream one is used by the computer to adjust engine operating parameters, such as fuel mixture. The downstream one is only there as part of the emissions system to determine if the catalytic converter is still functioning, e.g., the downstream sensor will not affect engine operation, but will prevent you from passing emissions testing.

That said, my guess is that the design and operating conditions are different enough that, unlike light bulbs, their lives may not be similar.
It depends on how tight your money is, and how much you prefer to have preventative actions at your convenience, vs. getting the max life out of a component. I myself would probably replace them both at once, particularly since the upstream one can hurt fuel mileage if it is declining in function, but not yet enough to trigger a CEL.

But, as I say, it all depends how important $40 is to you at the moment.
 

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I found with my SVT taht aftermarket 02's are too tall. If the header is struck and pushed back it makes like even tougher.
 
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