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Did I replace wrong 02 sensor the whole time ?

  • Thread starter Thread starter Killa
  • Start date Start date Nov 1, 2007

Killa

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#1
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I get under the car today and find out that 2 sensor on each side of exhault , next to tranny, what are those 2 sensor, I been replace 2 sensor that back of my car. and I thought that was 02 sensor.

1998 stang gt.
 

Winters98GT

Whoop...whoop-whoop-whoop-whoop...GANGNAM STYLE!!!
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#2
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KillaGT said:
I get under the car today and find out that 2 sensor on each side of exhault , next to tranny, what are those 2 sensor, I been replace 2 sensor that back of my car. and I thought that was 02 sensor.

1998 stang gt.
Click to expand...

sorry, Im honestly unsure to your question

There are four 02 sensors that connect to the midpipe......
 

the98stang

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#3
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The 2 rear sensors essentially do nothing. The front o2 sensors actually send important signals to your PCM. So yes, you have 4 sensors stock, but the 2 rear are worthless.
 

Killa

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are they all using the same 02 sensor ? can I bring the 2 rear ( new ) and bring to the front ?
 

Winters98GT

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KillaGT said:
are they all using the same 02 sensor ? can I bring the 2 rear ( new ) and bring to the front ?
Click to expand...


they proboly won't fit, youll need extensions
 

BennyBlown2v

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#6
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Winters98GT said:
they proboly won't fit, youll need extensions
Click to expand...

Not just that - the rear O2's and front O2's in our cars are NOT the same parts. In some GM's the front and rears are the same parts, but not for us!
 

lvmustanggt

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#7
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Front and back are different 02 sensor so do not move them back to front or front to back.
 

Killa

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all my part store they only carry one kind of 02 sensor. its not list for front or the rear, they told me that, they are all the same
 

Brute03

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#9
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no, they're not the same. the front and rear are two different part numbers
 

Killa

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I call napa, oreily, autozone, advance autopart, and the brand they only carry is BOSCH and all front and rear is same part # 13127. I call the dealer and they told me that, 2 are different part number, and its cost $96-$100 each, I cant spend $400 on those 4 sensor, cause I accident throw away 2 rear factory sensor away. Can any one tell me the right part number for front and rear sensor, How do you guy remove the front sensor ? thanks
 

lvmustanggt

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http://www.automedicsupply.com/catalog.php?&pkey=1385670

Check this website. If you go to autozone tell them you need 2 for before cats and 2 for after cats
 

281CI96Coupe

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the98stang said:
The 2 rear sensors essentially do nothing. The front o2 sensors actually send important signals to your PCM. So yes, you have 4 sensors stock, but the 2 rear are worthless.
Click to expand...


Actually, I beg to differ. When I had fault codes from my rear sensors, my car didnt run up to par...the heater circuits in the o2's were malfunctioning. So i bought new ones and took the MIL's off. Car runs a million times better with no CEL.
 

jstreet0204

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They are different part numbers only due to the length of the harness. They are however the same bosch 4 wire o2's and are interchangable. The different functionality of the front and rears is controlled by the PCM, not the part itself. This is why the part stores carry the same part number for front and rear.
 

Winters98GT

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jstreet0204 said:
They are different part numbers only due to the length of the harness. They are however the same bosch 4 wire o2's and are interchangable. The different functionality of the front and rears is controlled by the PCM, not the part itself. This is why the part stores carry the same part number for front and rear.
Click to expand...

as I was about to reply.... Thanks!
 

twogts4us

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#15
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jstreet0204 said:
They are different part numbers only due to the length of the harness. They are however the same bosch 4 wire o2's and are interchangable. The different functionality of the front and rears is controlled by the PCM, not the part itself. This is why the part stores carry the same part number for front and rear.
Click to expand...
Give that man a cigar!
 

Mike97gt

it doe snot
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The rear o2 sensors are just about the same and work the same as the fronts but what the PCM does with them is very different.. The front pre cat 02's are used for fuel trim adjustment and the rear 02's are used to monitor cat efficency.

BTW why are you replacing the sensors??? If it's for a check engine light you may want to do a full diag before you spend money.
 

Killa

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few month ago, my car suddently burn alot of gas , and exhault smell like burning gas and little of smoke, it throw a code so I went to autozone and check it, it turn out that my 02 sensor, I bought it and replace down stream one ( cause that wat I thought I only have 2 o2 sensor, i dint knew there was 2 upstream one), the code is gone and car ran great, until the other day I get under the car and found 2 more ( upstream , that look like 02 sensor ), so I want to replace that too, then I went to autozone and look it up then find out that is the same part, so i went home and try to install it , it wont fit, so I find out that 2 in the front are different from 2 in the back, I went and got my moneys back ( 3 month old 02 sensor and still can get full refund ).

https://www.automedicsupply.com/about.php?

should I go with motorcraft or denso or walker ? thanks

1. PRE-CAT LEFT
2. PRE-CAT RIGHT
3. POST-CAT LEFT
4. POST-CAT RIGHT

what those mean ? BTW I ran the car without 2 rear sensor is that ok ? any body knew that side of plug that I can screw its in that rear 02 sensor threat . my exhault alot loud and my rpm jumping around.
 
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