# 2011 335d code help...Newbie



## EBinOC (Feb 19, 2015)

Getting these codes. 2011 335d, about 108l on odo. Engine just started idling a little rough. Milage has been ok. Brief issue with limp mode during a very cold snowy day. Any insights, recommendations, fixes, or at least an assessment if this is something I can wrench on my self would be greatly appreciated. Thanks for helping a rookie out.

P101 Mass/Vol Air Flow A Circuit Range/Performance
P02D7 Cyl 6 Fuel Injector Offset Learning at Max
P02D4 Cyl 5 Fuel Injector Offset Learning at Max
P02CD Cyl 1 Fuel Injector Offset Learning at Max
P20EE Oxides of Nitrogen Catalyst Efficiency Below Threshold (bank 1)


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## KeithS (Dec 30, 2001)

You need to start reading the diesel boards. All except the last code I would say points to CBU (Carbon Buildup). A significant percentage of the posts relate to CBU. This will happen to every 335D, just when is the question. For many it will occur more than once in the car's lifetime. Except in very limited circumstances where you have all the needed 335D specific specialized tools and knowledge, cleaning the CBU is not a DIY procedure. 

The good news is BMW has a pretty good handle on diagnosing and correcting the problem. If you are over 100K miles, this will be on your dime. As very few have actually had to pay for the CBU cleaning themselves at this point the cost is somewhat a guess, but believed to be in the neighborhood of $1500. Once the cleaning is done the car really does run like new. 

Good Luck


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## EBinOC (Feb 19, 2015)

Thank you. I've read a number of threads on the issue. I had the feeling carbon might be the problem. I just need to find someone in MD who does that service. Otherwise, the car is fantastic.:thumbup:


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