2011 X5 50i oxygen sensor question
 

I recently purchased my 2011 BMW X5 50i with 153,000 mi on the clock. It was well maintained with $16,000 worth of receipts from the local BMW dealership in the last year and a half.. it looks great it runs great. But for some reason everyday, I get a check engine light with two reoccurring codes 2c2d and 2c2e. I see where about a year ago the oxygen sensors were changed out by the dealership and then trying to do the easy thing and fire the parts Cannon, I swapped them out for some Bosch oxygen sensors. Surprise no change in the reoccurring codes. I apologize if my question is redundant and has been asked before. I searched quite a bit before coming here..I've never owned a BMW before and all my past automotive experiences has been with ls powered vehicles. Interested in hanging around and learning more about these cars. Any idea of what I could looking to next that could be the likely a culprit, that's causing these oxygen sensor codes? Thanks in advance

Do you have a proper BNW dedicated scanner? It would be good to post the code description as well. There often is no easy answer to mixture related codes which is often the reason the car gets traded off in the first place. If the codes are actually for the oxygen sensor or circuit itself that is different than a mixture code. What do you mean by "powered vehicle" ??

I do have a dedicated bmw scanner and can post descriptions soon. Powered vehicles mean equipped with . LS powered aka LS engine on some GM vehicles or in Ford a Coyote powered car,etc

2c2d oxygen sensor before catalytic converter overrun check
.2C2E Oxygen sensor before catalytic converter 2, overrun check -

so 2c2d and 2c2e are right and left bank ?? and overrun means rich ? what are you using for scanner?

I have no idea whether one is right and one is left bank? That's kind of why I was coming here I'm pretty green to BMW stuff. A lot of these codes and their descriptions are absolutely nothing like what I'm used to from tinkering with GM vehicles. My novice brain was assuming that since those codes had the number two in them but they were both referring to the second Bank which would be the driver side I'm guessing? But even then it's just an assumption I don't know anything about bmws. I'm using a scan tool that I found in the trunk of this X5 when I bought it. It does seem to have live data to a certain degree it looks like I can monitor the O2 sensors it looks like some cheap generic Amazon or ebay scan tool but it seems to do the job

Autophix 7910 is the name on the front of the scan tool.. thank you again for attempting to help me I know it's a bit of a pain since I know very little at this point.

It would be nice if you had a laptop with BMW software or maybe the Foxwell scanner that some of the others here use so they could chime in. Definitely get yourself a copy of the repair information. The BMW software often has the repair/diagnostic info and strategies linked-in that come up with the related codes.
Especially since the car has been so well maintained at the dealership and there is a scanner in the trunk and you likely got a good deal there is a good chance that it will be not easy to find the problem(s) and/or the fix will be expensive. You might try running a can of catalytic converter cleaner to see what happens, might give some clues.

And use only brand name premium gas if you aren't already. I bought an E70 last year as a spare vehicle which I am pretty sure the previous owner was using regular and now have run about 6 tanks of gas through it and it runs better with every tank.

Yeah I agree I need some kind of better software. It has had brand new downpipes put in at dealership last year. Which if memory serves the catalytic converters are in the downpipes as well as injectors and coils and spark plugs and a whole bunch of other stuff all last year. As you said I have a feeling the reason they sold it to me is because of this reoccurring issue, despite them spending a lot of money to resolve it. The kicker Is the vehicle runs fantastic, it's a bummer the check engine light keeps coming on, because it seems like it's coming on for no reason. It runs exactly the same with the light on or off

First, the Autophix is the same as the Foxwell units, IMO. Looks the same. Chinese. These are genrally fine, HOWEVER a cable and a laptop with BMW software will give you access to far more. Inclduing the service manual. (Although this will *also* be a learning curve. It isnt as linear as one might hope.)


Second the code numbers have NOTHING to do with banks or whatnot. There was some rational, in German, many years ago but it is not really decipherable.



Google the code, then read a lot of info on them. Usually the first 'raw' translation will not mean much. Keep digging.


FInally, (and this is a WAG) I think you may be in for a world of hurt. SOmeone spent a lot of time and a lot of money at the dealer chasing this odd issue. They were still stumped after 14k.....


Two questions:



After you clear the codes, how long until they return?



Does HOW you drive it (highway, versus a lot of stop and go/accelerations) have any impact on how long this takes??


I know most people think "read codes, get a computer- tells you what part is bad" is the first path to take. IMO that path had already been paved with $14k of the prior owners money....


Report back

The TIS has a ton of good information on how the diagnostic codes are set, most is listed by P numbers though. Here is a sample, the flow chart didn't copy.

EXHAUST GAS SENSOR MONITORING > 5.3 NOX SENSOR DS LAMBDA SIGNAL > 5.3.2
LAMBDA SIGNAL MONITORING DURING OVERRUN (P229F)
General description
To eliminate the Nox Sensor monitoring concern, BMW included a diagnostic that monitors the response of the
oxygen measuring component of the Nox Ds Sensor during fuel cut.
If the test conditions are satisfied the signal is compared with threshold values. If the signal is above/below a
threshold a fault is detected and a preliminary DTC is stored. If this fault is detected in two consecutive driving
cycles, the M L is illuminated.
Flowchart
Fig 1: DTC Storage Flowchart (Lambda Signal Monitoring During Overrun)
Courtesy of

2c2d in hexadecimal converts to 11309 in decimal btw which looks like it could be a BMW fault code. The Bentley manual for the E53 shows the BMW codes and equivalent P-code but I don't know if there exists something like that for the E70. BMW diagnostic software (with TIS built in) might even show you the correct flow chart (and maybe even wiring diagram and diagnostic strategy) for the code retrieved.

After clearing the codes it varies as to how long it takes to return. Usually one to three drive cycles, sometimes I take it around the block once and it pops on. Sometimes I take it around the block three or four times and then it pops on. Style of driving doesn't seem to affect anything. And I agree this seems to be a deeper issue someone chased. I just wonder how deep can it be cuz man it sure seems to run and drive great. No odd smells, no smoking, it doesn't leak anything, no strange noises. Being a novice with BMW... From the outside you see a nice pretty car that looks very well taken care of on the inside and outside and a big fat stack of maintenance and repair records. And you think to yourself man this is a good buy somebody really cared about their car. And then you own it for a few days and you start seeing chinks in the armor..

I did see along with new downpipes and catalytic converters it got reman turbochargers installed last year as well. All this was done at a BMW dealership in Oklahoma called Jackie Cooper BMW

Before coming on here and asking the question I did quite a bit of exhaustive research on those codes and it said any number of things could be wrong with it. Vacuum leaks and exhaust leaks, spark plugs, oxygen sensors ,injectors, even saw one guy had a piston ring issue, you name it it was suggested that this code could be caused by it lol. That's why I ultimately ended up here hoping I could talk to some people that were experienced and maybe some have been there and done that

BMW v8s had an issue where injectors were mismatched- enough to let a cylinder here or there run very rich- car would run fine, but the engines would grenade when oil was diluted with the gas from these rich cylinders.


I bring this up NOT about your issue, but rather as an observation that 'it doesnt smell' or 'it doesnt smoke' or "runs great" is not a reason to ignore (or not be very concerned) about codes or CELs. Bad things can be happening.


Just an FYI.


Can you run a vanos functional test on the code reader you have? Slaggy VANOS solenoids/actuators can result in AFR issues, which can be very sneaky- it isnt a set thing, but at some parts of the RPM band, you are running rich. So it doesnt always happen the same. The fix is popping out the vanos solenoids, flushing them hard with carb cleaners and actuating the, with the proper voltage, then reinstall w new orings. Solenoids get fouled when people dont change the oil o time. A BMW specialty.



One final thing- but I am guessing you saw this- since BMW motors all share the same functions/componentry, dont focus only on "X5 w V8"... lots of other BMWs share these issues.


How many prior owners? All of them baby it, spend a ton of $$ and over-maintain it? Could have been a deadbeat owner in there. Also, BMW dealers can suck- the "BMW Maintenance" is notoriously poor- oil change intervals that are WAY longer than is healthy. Dont think because it was serviced at a dealer this buys you something. Its good that the serious repairs were at a dealer and may have a warranty on this work

It was a one owner vehicle that a loca.dpctor owned...I agree the issue shouldn't be overlooked just because it seems to run so good. But to a simple man view point it almost wants to trick you. I have 4 other vehicles I have as daily drivers, I bought the X5 more as a fun little toy to tinker with. So I'm happy for it to sit there until I get it straightened out. I will look in that scan tool and see if it will do a Vanoss test. I guess in the worst case scenario even if I can't do that test I could always just pop them out and clean them up real good as you suggested. I did see in the warranty work that the heads were pulled off and redone last year as well because they suspected a valve seal issue. And the cooling system hoses and such were redone at the same time. I was told when I called the local dealership that all the work they performed last year was still indeed in warranty. But they couldn't tell me whether the issue I was currently having would be covered by that warranty.. and if I drop the car off I could be subject to fees if it's not.... In the past tinkering with cars I've had a lot of success being a part of forums like this because a lot of you guys have been there and done that. I will certainly tinker with that Vanoss situation over the weekend. And again I appreciate your help thus far

If you haven't already, have a look at HomerlovesBeer thread. It might take some commitment on your end but nothing is impossible ;)
Do you not already have a diagnostic laptop for working on your "powered" cars ??

I do have a laptop that's running an old version of HP tuners. But I looked at the HP tuners website and they don't offer any support for BMWs. I even sent them an email as to why because they do Lexus and even Mercedes-Benz and they said that there's not a high enough demand for them to put out a version for BMWs LOL. I will look up that thread that you mentioned. I bought this BMW knowing it would probably be a bit of a challenge but I did underestimate it a little bit I think LOL. As you mentioned earlier if the dealership couldn't get it figured out after 15,000 plus dollars, chances are is probably not something simple. That a simple guy like me will figure out easily. But I'll keep plugging away at it and see where I get. Thanks again for your help

I ran across this in the TIS (which I obtained from a member here and am ever so grateful even though this is for the newer facelift which mine isn't ;) )

I've recommended Stabilant 22A on this forum before but it came from a very small Canadian company back in the day, for a niche market, so I'm surprised to see it now used and recommended by BMW.

The oxygen sensor gets it's reference from the air space around the wires going into it, if there is a sleeve around those wires that is sealed to the sensor then the reference comes from the end of the sleeve but it sounds like now the sleeve is sealed around the connector as well ?? Are the connectors not sealed then?? Under the heading of "bizzare things maybe not thought of or tried" maybe cutting a slit in the sleeve is needed ?


3.0 ELECTRICAL CONTACT ENHANCER AND CONTACT CLEANER > ELECTRICAL
CONTACT ENHANCER
Stabilant 22A evaporates and leaves a thin polymer film which is conductive between the mating
surfaces, while staying non-conductive between adjacent pins. At the same time it prevents the
formation of any further harmful deposits.
Wurth Part No. 893622 (Stabilant 22A)
Note 1 : Stabilant 22A must not be used on Oxygen Sensor connectors. To function, oxygen sensors
require a flow of oxygen through the terminal connector to the sensor element. Stabilant 22A will affect
this flow of oxygen, and will result in irreparable damage to the sensor.
Note 2: Stabilant 22A must not be used on plug connectors which carry fiber optics. Stabilant 22A may
migrate to the fiber optic and attenuate the optical signal.
3.0 ELECTRICAL CONTACT ENHANCER AND CONTACT CLEANER > CONTACT
CLEANER SPRAY
Use to clean electrical and electronic components of dirt, grease, etc. Will not harm components or
epoxy coverings. Allow to air dry. Do not dry with shop air supply as this may contaminate the connector.
Wurth Part No. 89365 (Zero Residue Electrical Contact Cleaner)

Those codes are pre-cat O2 sensors for both banks.
Overrun means closed throttle while coasting. DME shuts off fuel under these conditions and O2 sensor output should be near zero. You may have leaking fuel injector(s) or oil blowby getting into the exhaust that O2 sensor sees. Use live data on a ODB2 scanner and look at O2 sensor voltage while coasting.
Too much air might cause this also. Does throttle close completely? Any vacuum leaks between TB and cylinder head?

The 50i's are massive oil consumers. How much oil does yours use?

https://bmwfault.codes

Wanted to update on a resolution...did some digging and found the driver side air intake was not fully pushed on. So i slid that on and secured it. Didn't really fix all of the issues but it was a good find. I remember the previous owner saying they had recently replaced both O2 sensors with Bosch brand. Which I had heard good things about that brand. I did pull those O2 sensors and indeed they look brand new. Just for a hunch though I ordered two brand new OEM BMW O2 sensors off of eBay. I installed them and instantly all of my issues went away. Black exhaust tail pipes, would look like black fuel spitting coming out the tailpipe and getting all over the back of the vehicle, the check engine light coming on all the time everything seems to have been resolved by putting into OEM O2 sensors and putting that air intake hat on the driver side. I did notice when I pulled it apart there was about a tablespoon of oil in each air filter housing... I've just been keeping an eye on the oil level and keeping it topped off. I guess these vehicles just really appreciate OEM sensors. It's been running great for about 2 weeks now

So wanted to mention at the local Jackie Cooper BMW last year there was over $16,000 spent on repairs. New factory downpipes, rebuilt turbos, they took off the cylinder heads and redid those, also coils injectors and spark plugs as well as other miscellaneous things.. I know the total it seems 16,000 I just haven't gone through the stack of paperwork fully.. so it looks like a previous owner spent a lot of money on upkeep

Well that is good news! :)
If the O2 sensors are getting their reference through the connectors then maybe watch out not to spray any engine cleaner or what not around in that area that might poison the sensors again.

Will do..thanks again for your efforts in helping me. I'm an older car guy and I know that a lot of online efforts go unnoticed. Now I'm onto other X5 issues. I thought I had a driver side front wheel and tire out of balance. So I installed brand new wheels and tires and had them all balanced two different times. Still on the highway about 55 mph if I give it a half throttle or more the dash and the steering wheel and everything shake violently. But what's weird is from a stop I can floor it and it can go through all the years smoothly no problem. For some reason there's something about going heavy throttle at almost highway speeds. That causes a very bad front end vibration. Starting to think it might be the engine mounts or transmission

Was there any abnormal wear or cupping on the old tires? It could be something with the front suspension or does it seem maybe possible it's coming from the transfer case?

No sir the old tires looked fine ..I just moved onto other wheels and new tire to totally rule that out as the culprit. If I had any critique it looks the lower control arm bushings could use replacing but they're not just totally torn through. It just kind of boggles with my mind that from a stop you can floor it and it pulls good and strong and clicks through all the gears without issue. But on the highway or higher speeds if you floor it can almost shock the drivetrain it starts shaking like crazy until you let off the gas. It almost feels like torque steer except for the wheels aren't being pulled out from under you. Engine or transmission mounts there symptoms sounded very similar to mine. But I also read that the n63 xDrive engine mounts are really difficult to replace. Which is not good news.. I welcome it to be anything else

Puzzling to me because it's usually at higher speeds at a higher throttle percentage. And it's almost like you feel it more in the dash and then you do in the steering wheel or the gas pedal. You do feel it in both of those things to a certain degree but man that dash feels like it's going to shake right out into your lap. I guess it could be the lower control arm bushings but I would have never guessed they can cause such a violent shake

I really can't see it being engine mounts but if others have had that then I guess it's possible. Why not go through the suspension first (or at least the control arms, I think they are the same setup as the e53) if you see some problems there anyway.

Sound thinking for sure, I did notice no vibration at idle or upon startup or anywhere else. It seems to be throttle and mile per hour dependent. Like at 45 mile an hour if I give a half throttle it shakes violently but the second I let off the gas the shaking goes away. But it certainly couldn't hurt to go through the front suspension like you said it can only make it better vehicle even if that isn't the cause of the issue. Still learning about BMW stuff.How do the lower control arms work on these vehicles? Are they serviceable can the bushings be pressed out and new ones pressed in? Or is it like some vehicles where it's easier and cheaper to buy a whole brand new lower control arm?

I have only done the E53 ones and pressed the bushings in/out. I think the E70 is basically the same but heavier duty.

Cool I jumped on FCP Euro and they had a small front end refresh kit for less than $500. Had the lower front control arms and the lower front rear control arms. Can't beat that go ahead and do everything while I'm there both sides. No having to press in and out ball joints or press in and out bushings. Just do a part swap and move on

1. Be VERY careful with counterfeit parts on ebay (and vurtually ALL other sources)... it is a very large issue with plugs, injectors nd O2 sensors


Google it.


They copy the part, label it with Bosch, copy the yellow Bosch box and packaging..... some very prominent companies have been fooled into selling these copies.



I dont buy any car parts on ebay.





2. Lower control arm bushes - aka Thrust Arm bushings are very very common failure points on BMWs. However the classic symptoms is 45-60mph, at light training braking, you get a juddering. YMMV. Good news is that yours prolly need it anyway, so not a waste of $. Yes you can press out bushes- but I would only do that once on an arm. for future references.