First off the car is a 1995 eclipse GS-T

I bought an upstream o2 sensor althoughI didn't really need one( got a hell of a good deal on it ) and I need a downstream o2 because the guy that had the car before me cut the stock one. Will an upstream o2 sensor work for the down stream? I'd assume an o2 sensor is an o2 sensor, but was not sure if the harnesses were different or if it was possible to just wire it in.

 

any input?

 

Guess not

 

No sir, the upstream and downstream are non-reversable. I forget why, I just remember that you can't for some reason, lol. What a crappy reason to give you, I know, sorry.

 

Oh, now I remember, but it has nothing to do with it's internal wiring or even the plugs, lol.

As you might know the front is used to keep the motor stoich, while the rear is just to monitor the cat converter. Aside from that...dunno.
I do hope that there are differences though because there's ususally a price difference between the two and are stated for one or the other locations and not either one.

 

Alright thats all i needed you are the man Silver. I just have a front one and it was only like 10 dollars ( brand new ) so i'll just pull the front one out replace it and buy a downstream one. What if you have a test pipe there is it pointless to run an o2 sensor?

 

Lol, yeah, the rear o2 will just send a fail code and the CEL will light up. You can just leave that one alone if it's not giving a CEL.

 

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thats what the $4 o2 fix is for

 

$4 O2 fix?

 

What is this $4 dollar o2 fix and its throwing the code for the rear and I want the light to go away.