O2 sensor replacement and alternatives

[Houstonbuckeye]

My light saying, Check Engine Soon, came on today. (42000 miles) I suspect the O2 sensor.
Does this light indicate a bad O2 sensor or could it be something else?
Is there some way to check whichsensor is bad or should I just change alll of them figuring that if one goes bad, then the second one can't be far behind?
Stan

[Dave07997S]

Originally Posted by Houstonbuckeye

My light saying, Check Engine Soon, came on today. (42000 miles) I suspect the O2 sensor.
Does this light indicate a bad O2 sensor or could it be something else?
Is there some way to check whichsensor is bad or should I just change alll of them figuring that if one goes bad, then the second one can't be far behind?
Stan

It could be other things...get a $80 scan tool and read the codes unless you got a buddy with one.

Dave

[pbonsalb]

02s are supposed to last longer than 40k miles, so get the codes pulled using an advanced scan tool with BMW specific capability. Go from there.

[Dave07997S]

Originally Posted by pbonsalb

02s are supposed to last longer than 40k miles, so get the codes pulled using an advanced scan tool with BMW specific capability. Go from there.

I had 2 go out...before 30k miles. One before primary cat and one post...

It could have been from them being damaged when the test pipes were put on. I saw how they did it, they unclipped them and dropped them with the OEM xpipe, but who knows.

Dave

[texastate]

Originally Posted by Fen335i

One of my pre-cat 02 sensors went out this week as well. I called about 5-6 places and found that ECS was the cheapest at $148 for the Bosch branded sensor. From what I was told, Bosch makes the OEM 02 sensor for BMW, so you might as well buy the cheaper Bosch sensor, since it's literally the same thing....and about $40 cheaper than the OEM one. (ESC was selling the OEM one for about $190)

I know this is an old quote but which side is Bank 1 -1-4 cyl. when looking at the exhaust from under the car? I'm going to buy one Pre cat as I got a P2297 Bank1 - Sensor 1 error on my Autel scan tool...

[texastate]

I don't know why i'm confused but both front and rear 02 sensors for bank 1 and bank 2 are underneath the car and not accessible from the engine bay right?

[edu09]

Originally Posted by Dave07997S

It could be other things...get a $80 scan tool and read the codes unless you got a buddy with one.

Dave

any brand of code reader you would recommend? I need to buy one for myself but don't have any idea where to get a reliable one

[pbonsalb]

Originally Posted by texastate

I don't know why i'm confused but both front and rear 02 sensors for bank 1 and bank 2 are underneath the car and not accessible from the engine bay right?

They are under the car, just before and just after the first set of cats.

[texastate]

Originally Posted by edu09

any brand of code reader you would recommend? I need to buy one for myself but don't have any idea where to get a reliable one

This is an excellent one.. Just got it last night.. great software support. Downloaded firmware updates from the AUTEL site easily and good windows support.. USB to computer detected fine and comes with a decent instruction manual (also PDF supplied on support CD).. Definitely recommend..

http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

[edu09]

Originally Posted by texastate

This is an excellent one.. Just got it last night.. great software support. Downloaded firmware updates from the AUTEL site easily and good windows support.. USB to computer detected fine and comes with a decent instruction manual (also PDF supplied on support CD).. Definitely recommend..

http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

Man yours looks like a pretty good one, I just bought one at auto zone and worked ok but yours looks much better, I paid $50 for mine, attached a picture
It is a simple one but helped me to identify a couple of error codes from my O2 sensors

[pbonsalb]

Launch makes some good inexpensive ones as well. I paid about $70 for one.

[happos2]

Originally Posted by texastate

I know this is an old quote but which side is Bank 1 -1-4 cyl. when looking at the exhaust from under the car? I'm going to buy one Pre cat as I got a P2297 Bank1 - Sensor 1 error on my Autel scan tool...

I believe 1-4 (bank 1) is the passenger side. Somebody can correct me if I am wrong though...

Originally Posted by texastate

I don't know why i'm confused but both front and rear 02 sensors for bank 1 and bank 2 are underneath the car and not accessible from the engine bay right?

Bank 1 and Bank 2 O2 sensors are under the car. Bank 1 is passenger side, bank 2 is driver side (again, please correct me if I am wrong someone). You have two O2 sensors (per bank) underneath the car, one pre-cat and and one post-cat. You will need to get jack up the car and get underneath when installing them...

[texastate]

Originally Posted by happos2

I believe 1-4 (bank 1) is the passenger side. Somebody can correct me if I am wrong though...




Bank 1 and Bank 2 O2 sensors are under the car. Bank 1 is passenger side, bank 2 is driver side (again, please correct me if I am wrong someone). You have two O2 sensors (per bank) underneath the car, one pre-cat and and one post-cat. You will need to get jack up the car and get underneath when installing them...

Ok.. Can anybody confirm that Bank 1 - Cyl. 1-4 is on the passenger side??

[IMG]

Originally Posted by texastate

Ok.. Can anybody confirm that Bank 1 - Cyl. 1-4 is on the passenger side??

That is correct Sir!

[VictorH]

Trying to remove my oxygen sensors today. The electrical connections for the fronts sensors are easy but I'm having trouble pulling the rear sensors. How do I disconnect the connectors for the rear oxygen sensors (the ones behind the primary cats). Thanks

[C|3R1C]

Originally Posted by VictorH

Trying to remove my oxygen sensors today. The electrical connections for the fronts sensors are easy but I'm having trouble pulling the rear sensors. How do I disconnect the connectors for the rear oxygen sensors (the ones behind the primary cats). Thanks

If I remember correctly it's the smooth locking mechanism with a tiny clip on each side. If so, I take two tiny tiny eye glass flat heads and carefully slip them under each "tongue" clip to unhook them from each nub, then gently pull the connector apart. I'm sure bmw has a fancy way of doing it.

[VictorH]

That worked, thanks

vah

[pbonsalb]

The rears just pull apart. No need for any tricks or tools. That connector has been in use since at least the mid 90s.

[MFKN3]

Originally Posted by pbonsalb

The precat 02, Bosch 17039, is about $65 shipped on ebay, but with some searching, you can find them for about $55 shipped. This is actually a little cheaper than the best price I have seen for the post cat 02.

How did you go with the $50-60 sensors?

In my quest to find a local vendor, I didn't find any under $100 on eBay but they were on alibaba for $60. The vendor told me they are imitations, yet have the bosch logo's etc on the barrel, but no bosch box. They said they test them and offer 1yr warranty and supply many distributors in the US and Germany.

Not sure whether this is alarming or not, but for an expensive car I think I will be sticking to a reputable supplier.

[gimmethemuumuu]

Go with Bosch for O2 sensors. No need to buy Genuine BMW. And definitely stay away from those imitation ones.

[hoeferland]

For sure, I just ordered two primary Bosch replacements and will post results once I've got them on the car.

[C|3R1C]

Originally Posted by hoeferland

For sure, I just ordered two primary Bosch replacements and will post results once I've got them on the car.

Look forward to your results!