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Discussion Starter · #1 ·
hi!!

i think my pre cat helper side o2 sensor is burn due of a short on body and all wire together

i still have my post cat sensor in my garage do you know guys if it will do the job or if it not the same type of sensor

the only thing i know is the post cat o2 wire is shorter than the pre cat sensor......not a problem for me!!
 

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Umm, not quite sure what you're getting at here.

The pre-cat and post-cat sensors are the same model (AFS75), so they can be installed in either position.

However, if you are asking if the post-cat O2 sensor will do the jobe if the pre-cat sensor is fried, the answer is no. The pre-cat sensor is used for adjusting the fuel trim, the post-cat sensor is only used to monitor the function of the catalytic converter.
 

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Discussion Starter · #3 ·
mmm the question is.... if i put the (removed) post cat sensor at the place of the fried pre cat sensor....!
 

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It will work just like a pre-cat O2. Like you already noted, the only difference is the pigtail length; the pre-cat and post-cat sensors "sense" O2 the same.

For that matter,most all nb 4-wire (heated) O2's are the same, with the difference being the pigtail length and connector style, and possibly heater wattage (not sure). 2 of the wires are the + and - for the heating element, 1 is for the actual sensor element and goes to the PCM, and the last is an external ground lead.
 
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