[grimma]

Hello everyone,

I have F11 535d, 2011 which is European version with bi-turbo and 313 hp. The vehicule has 112500km. While I was driving other day on the motorway there was suddenly yellow engine light illuminated. :yikes:

I have my WIFI OBD2 scanner which I plugged to check the code, because car did not gave me any messages on "idrive".

The fault code was P115D. I could find on the internet that the code means: The diagnostic function compares the calculated air mass with the measured air mass.


I have first cleaned my air filter which is really dirty and to be replaced. it is already fourth year.

I have cleared the code with my iPhone application but after some driving it would come back.

Finally today I have removed my Mass Air Flow sensor which is found on the top of the engine. You can see it once the engine cover is removed. It is located downstream of the air filter. I think it can be removed with ratchet and T25 or T30 bit.

I have cleaned the MAF sensor with my uncle's home made vodka.:rofl: I am sorry I did not have any isopropyl alcohol, but this one served very well.

Once I have plugged the sensor and re-bolted everything back, I have started the engine and the yellow engine light just disappeared. :thumbup:

I have rechecked with my iPhone app to see if there is any active fault code ant there was just the same code stored but not active like.

I have wrote this guide to help other people if they will have this P115D fault code.

I hope I have correctly uploaded some photos to see the thing clearer.

 

[grimma]

Hello everyone,

I need some help. The engine yellow light came back, with the the same code P115D. Every time I do a reset it comes back in one or two days. I have installed new air filter. Is there a way to confirm a faulty MAF sensor? i have working ISTA D but i am waiting for my ENET cable I ordered few days ago. I really dont want to buy a new MAF sensor plug it in and have the same error code in two days. Please advise.

I have opened a MAF connector cleaned with brake cleaner and inspected no wire damage found. I dont want to drive for long with the code because I dont want my DPF or Turbos to fail. I fsome one could explain me the details about the code P115D it would be very cool.

If any of you people have some diesel knowledge please help.

Thank you,

Best regards,

 

[Danielh1]

Did you find any solution for this? I have the same problem, same code - P115D.
Car runs good!

 

[grimma]

Hi Danielh1,

Since last update I have replaced EGR valve with BMW Stealers but the fault arrived the next day. They told me my EGR valve was indeed defective because I was also loosing engine coolant on the EGR valve. A very slight loss. every 2 and a half months I had to add 1 liter usually i would have add coolant message in the morning. The reason why I had the P115D or via ISTA/D was 290900 I think. It is about the measured air is not the same as calculated air by DDE. The BMW said that was due to carbon build up in my intake because this is a Direct Injection engine and it is common for them in you dont drive them hard to develop this issue. Also they wanted charge me for walnut blasting of my intake about 2500 Euros. I declined that.

This morning I took my car to a local garage for Hydrogen carbon cleaning. They put the machine with the Hydrogen tube infront of my air filter while engine is working and leave it like that for 35 minutes. they did occasionally rev up to 2500 rpm. When I took my car back they told me to drive it on the motorway in the high rpm for at least 30 km. Which I did. The service engine light was still present.

After that I have deleted the code via OBD2 application. I will see if the service engine light will return and I will update. I think it is more smooth on idle now but it could be a placebo effect.

If this does not work next step will be a can of Liqui Moly diesel Intake cleaner to my inteke to clean it up. As I understood the code is due to reduced intake runners due to carbon build up.

What did you tried until now to solve the issue?

 

[Danielh1]

Thanks for your answer! :thumbup:

I got this code yesterday. I did a reset and the CEL has not lighten up yet. Hopefully it will not come back..

If i've understod it right the P115D is the MAF measures higher air flow than it acctualy should be and P115C is it measuring lower than it should.

If it comes back I will start with cleaning the MAF-sensor, you have still not changed your MAF?

Mine is a 530D, 13500km, year 11.

Edit; Just a thought - If the air mass flow is higher in the MAF-sensor (if sensor works), then it should not be carbon built up? Shouldn't that give lower air flow?

 

[grimma]

well if the intake runners diameter is smaller the air would actually had to increase the velocity in order to supply the same mass of air as it would be with the larger intake runners diameter. This is why we have code P115D and no P115C.

I strugle with this code already few months. Since i did a HHO carbon cleaning this morning i hope that it removed deposites.

I did already cleaned my MAF but it seams that the MAF is not the culprit. And especially not on your car , when you have only 13500km. That is still new for me. what you did is that you were babying that car as I did mine. With the EGR (soot) + crankcase ventilation in the intake (oil) there is carbon build up in the intake.

this cars should be driven hard at least once per month.

 

[Danielh1]

Okej, I understand!

I missed a 0, the car have 135000 km The CEL lighten up again, so something is not ok. I have seen some pictures of intake / EGR-valve and they seems to get really clogged up.

Maybe the best way is to remove intake and clean it with something.. I will do an update, but right now I dont have the time to spend on the car.

Please tell me if you have any luck with HHO cleaning or Liqui Moly

 

[grimma]

Hi,

It did 3 days without check engine light. subsequently I have erased the light with my iphone app.

I did reseted all adaptations for air mass and exhaust with ISTA/D subsequently and erased the 290900 error. The HHO cleanning helped a bit even my wife noticed car idled smoother after, or we are just under placebo efect.

The garage which performed HHO clean did not even removed my air filter. they just fitted HHO hose infront of the air filter.

I will have to take a long drive tommorow but in few days I will spray a can of liqui moly in the intake manifold. I will update for the results.

Does anyone know is it safe to remove intake air temp sensor to use the hole for liqui moly nozzle in order to spray the cleaner inside? sensor is just in front of the throttle flap. Car has to be run on 2500 rpm thou.

If my egr valve cooler is clogged how can introduce the cleaner product inside?

as per ISTA, for this code first thing is clooged air filter second is clooged Egr cooler.

Sent from my iPhone using Bimmerfest mobile app

 

[Danielh1]

Saw in a facebook group this could be the throttle body, that would make sense to me. She did not get any code for throttle body, just high air flow. Bmw first changed egr valv and sensors, then throttle body wich solved it.

 

[grimma]

I drove 1000 km last night, without light and this morning i have it back! tomorrow i am throwing in a LM intake cleaner can in side! will update results!


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[grimma]

I had light only that morning above written, after it dissapeared by it self and I still did not had it back! I hope it will stay like this! It was after use of HHO only.


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[Bruno81]

Hi,
You need to check the O2 sensors (oxygen sensor, lambda sensor). This is often an incorrect measurement of incoming air. The MAF sensor measures the incoming amount of air, and the o2 sensor measures the amount of air in the exhaust. If the data does not match, it often shows a MAF sensor error.

 

[Kam15]

Hi guys I got the same issue code P115D and 290900 comes on every 3 days after reset and change of air filter also cleaned the Mass flow sensors thinking of just taking it to Bmw uk as local garage could not finger out what the problem was . I own a bmw 520d msport 2014 had it for a year it***8217;s done only 35k

 

[Kam15]

This is what i got from Diagnostic reader

 

[MunichMark]

Häsch Dini Ovo Hüüt scho Chaa ?

Grüetzi,

If you speak German I would only suggest you go to the F10 German Forum. There you will find many similar situations. This is a very common occurrence at your KM's especially if a lot of short non-spirited driving (wie in der Schweiz).

Just search using Verkokung and especially EGR Rückruf.

I hope you did not have to pay much to BMW as this is a well known problem especially due the recent recall on the EGR and related systems.

Biggest issue is the entire Inlet System to the Valves needs to be cleaned (there are several methods but do not include injecting anything into the engine while running !!!

Also, very important is to reset all adaption rates BEFORE starting up again after the cleaning otherwise you end up with the situation you seem to have now ( Drallklappen wahrscheinlich außer sync).

Mit freundlichen Grüßen, MunichMark

 

[Danielh1]

Update: I cleaned the MAP-sensor, this is 4000km since and still no engine lamp. It is placed on the intake and easy to disconnect.

 

[Kam15]

Hi guys took my bmw in to the main dealership they have kept it as it may be covered by bmw under EGR RECAL. My EGR cooler has got a leak in it let’s wait and see what happens as the part is not available coz of the recall they said that they may replace with a bmw courtesy car let’s see what happens


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[Kam15]

Just got the good news BMW is going replace the EGR no payment from me


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[johnboy7171]

Help

Hi Guys, I am new to the forum.

I have a 2010 520d Auto F10 with 120,000 miles.

I have been having whats seems to be the same problem.

My engine management light started coming on around a year ago without any running problems whatsoever. The code read said it was the air mass meter (or air flow related) so I replaced it however the light came on again, and again there were no running problems, and in fact my MPG on a run was getting into late 50's, even 60 mpg.

Since it was running fine I didn't do anything about it but was just annoying that there was a light on.

Last month after some 6 months or so the car stalled in traffic, Upon restarting, initially the car went into reduced power/limp home mode for a few seconds and then was all normal again, except that the EML was still on. For the next few days I noticed very slight hesitancy at a steady speed which reminded me of a previous car I had where the EGR valve needed cleaning.

I took the car to my local garage who said the code was 290900. As such I had a new EGR valve fitted, the cooler was checked and found to be OK with no obvious leaks, I also had a new air filter and oil filter, and a smoke test done to check for any air leaks.

The smoke test showed some leakage around the intake manifold so when the garage went to replace it, they found the manifold itself was fine, but the flaps needed to be changed, which they then did and fitted a new gasket.

However a few days later the EML came on again!! Code read still says 290900 as per picture.

The garage suspects that it may well be the EGR cooler after all as apparently there are some flaps there too which may not be functioning correctly (and which would not be known when they inspected it).

I am reluctant to keep throwing parts at it, especially as the car runs fine. On a couple of occassions it has had lumpy idle for a second or 2 but no limp home mode, just the EML is on.

I spoke to BMW customer services and my local dealer who both said that there car is definitely not covered by the recently expanded EGR recall.

The local garage has suggested blocking the air intake and deleting the egr valve from the ECU. I am really not sure about this as its a work around and doesn't solve the initial problem, as well as it possibly having MOT implications.

Does any one have any ideas as to what the problem could be or what I should try next? Its driving me round the bend!

Thanks for reading!

 

[MunichMark]

520D’s especially if driven shorter distances suffer from “Verkokung” (Carbon Soot buildup) quite often starting around this amount of KM’s.

To do everything right the whole system needs to be cleaned professionally, not just one piece at a time. Then, and this is important, all adaption settings reset BEFORE starting up again.

DIY is possible but it’s a huge mess. This means up to and including the Valves, most do Walnut Blasting but manual cleaning is possible if patience allowed. Any leaks or compromised Hoses will cause continued issues.

Blocking the EGR requires special coding also not to mention it’s illegal, at least in the EU.

If starting issues and the lumpy idle when cold still exist could also be related to the Glow Plugs and /or Relay Control Box... These Boxes fail a lot on these Cars.