# 95 O2 sensor/sensors 1? or 4?



## TACOMAPINOY_M3 (May 13, 2004)

Trying to replace my oxygen sensor. Last weekend I went under the car and only see one O2 sensor before the catalytic converter, and didnt see any on the exhaust manifold. I went online and look for a replacement part and kind of confused, I guess theres 2 types of engine that was release for 95? S50 and S52, can somebody tell me how to ensure which engine I got.


Thank you


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## Pinecone (Apr 3, 2002)

95 only has one. Only the S50 engine for 95, and with OBD 1 emissions controls so only a single sensor.


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## TACOMAPINOY_M3 (May 13, 2004)

Thanks Terry


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## SoloII///M (May 16, 2003)

TACOMAPINOY_M3 said:


> Trying to replace my oxygen sensor. Last weekend I went under the car and only see one O2 sensor before the catalytic converter, and didnt see any on the exhaust manifold. I went online and look for a replacement part and kind of confused, I guess theres 2 types of engine that was release for 95? S50 and S52, can somebody tell me how to ensure which engine I got.
> 
> Thank you


Terry got it. Just one.

It is a royal PITA to get to, though. I have one of the universal O2 sensor tools (hardened deep socket with a split in it for the wire) and I couldn't get it off using a breaker bar - because there isn't room to get the breaker bar up there. I had to get a 1" box wrench on the tool to loosen the sensor. It's either that or drop the exhaust.

Good luck.

John


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## Pinecone (Apr 3, 2002)

Thanks for letting me know. I will plan on changing the exhaust when it is time to do the O2 sensor.


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## rwg (May 10, 2002)

There is a thread in the DIY forum about replacing them that includes a link to Bimmerforums that had a lot of discussion from people who had done it - apparently the are tough to get out, you should spray it with penetrating oil the night before, and if you have a torch, it's safe (and sometimes necessary) to hit it with a torch to break it loose.


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## Pinecone (Apr 3, 2002)

Thanks. I wil keep it in mind.

I have the torch.


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## Bruce (Dec 24, 2001)

I had no problems getting mine out. It took about 15 minutes (including jacking up the car).


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