Need some insight.
 

I am a little confused I read too many conflicting reports. I have a 2000 Boxster S I recently got code P0153 so I changed the 02 sensor on the passenger side of the car and I still keep getting the code. My car is an American car did I change out the wrong sensor??

I had that code (bank 2). Changed one 02, I think it was a Walker. Still kept happening over and over. Other three 02's (2 post, 1 pre) were replaced...problem went away for good. I think my mechanic uses Bosch.

The replacement 02 was a Bosch I don't want to needless replace all the sensors if they are still good.

Seems to me that its like an ecosystem. Replacing just one can have a knock-on effect. Sometimes it works sometimes it doesn't.
But I'll leave it to the actual mechanics who post on here regularly.

More than one O2 sensor going bad at a time is highly UNLIKELY unless you know of a specific reason for it's occurrence.

The most important thing to remember when getting an O2 sensor CEL code is it means (and only means) the value being reported is out of range for circuit that particular O2 sensor is on. Period. It could be b/c sensor is bad / or fouled, cat is bad (if S2), or wiring at sensor is bad, wiring before sensor is bad, MAF bad (if multiple codes for each sensor), etc., etc.

Use a multi-meter to test the sensor itself before replacing. If fine, then start looking upstream from there starting with the wiring.

And finally, Bank 2 on a Boxster is on left side when seated facing forward. S1 is pre-cat, S2 post.

:)

As a former Porsche tech, I can tell you with 100% certainty that you must replace all 4 o2 sensors. Perfectlap is correct, sometimes you can get away with replacing one but usually you end up having to replace all 4.

OP doesn't even know if his one O2 is bad and you're blanketly advising to replace all 4 sensors. :eek:

Honestly, this ranks up there as one of the more irresponsible posts in recent memory on this board... unless you are being facetious which cannot be inferred at all from your "qualifying" disclosure.

Oh my...

I agree that changing all 4 sensors doesn't make any sense. I did rectify the code the sensor was giving but I am still getting code 0410 and 1411. I am assuming that since I did work on the throttle body and the AOS maybe one of the vacuum lines came loose or cracked due to manipulating them. Any tricks for a home mechanic without a smoke machine to check for leaks?

I *think* you can run without the two rear O2 sensors -- you could disable those (zip tie them up) and see if it goes away? If not -- replace the last front run.

I would also clean your MAF.

Mike

you can try spraying carb cleaner or similar which has alcohol in it. If your idle changes -- there
is a leak where you sprayed.

Caveat -- you are spraying a flammable substance on a combustion engine.

I take no responsibility for anything :-) Although I have successfully done
this on a 928.

Mike

I think that was said under the inference that the one 02 sensor was determined to be the root of the issue. I've heard the same advice from other mechanics.

My personal mechanic tried all other avenues to no avail and replacing the other 02's was done as a last resort but did solve the issue...plus the labor to diagnose.
Porsche says the 02's are life time parts but my car was nowhere near 100K miles when this issue came up.

Your right. I got caught up in the O2 sensor details.

Redeye, my tech and I were fiddling with this same issue on my car a while back and he made two important statements to me that are worth passing along:

1. The computer throws codes that are not completely indicative of a correct failing part. I got a fouled MAF reading that was actually a burned tip on one of my 02 sensors. Replacing the oxygen sensors cleared the MAF errors. Go figure.

2. Replacing one 02 sensor will give very sensitive readings and the others, aged with heat and probably carbon, will provide dull readings and the computer will hunt for another reason to throw a code. This is why all four are replaced. [As I read your posts I see you're no stranger to a motor and it's components, so I'm just sharing what he taught me. I'm sure you already knew this.]

I replaced all four of mine when this same issue cropped up and it was worth the $450 I paid for all new sensors. Within about a half hour of driving the performance increase was noticeable and my fuel economy improved.

thanks for all the info I will try to see if there is a vacuum leak first. If I can find what is causing the first 2 codes maybe that will end up clearing the issue of the O2 sensor