All, Cheers! I haven't been here since my days with my 05 JCW. She went to Mini heaven and I've since purchased a 2015 S with the 2 liter. 75k miles on it for 10k. Car was in really good shape, does not appear to have any oil leaks, etc. However, the previous owner (do not have a way of contacting them) ended up putting a replacement exhaust from the downpipe back on the car. I get codes and the car runs a bit rough (seems more so when it's warm out).

Here's the facts I know:

1. The muffler they replaced it with was 1/3 the size of the OEM muffler, therefore it was obnoxiously loud.
2. I've since replaced that muffler with an OEM replacement stock muffler I found from a company online down in Texas for $350, since I was not able to find anyone in the Dayton, Ohio area that could even service the muffler. Everyone told me I had to go to the dealer. Well, when I went there, they only wanted to sell me the entire thing - welded as one piece downpipe back for $3,500 plus labor to install.
3. It appears they left the factory resonator installed (if that's the piece between the muffler and downpipe).
4. For whatever reason, it looks like a second air flow sensor was installed adjacent to the factory one. I'm not sure what this is about? I've tried using either/or but no change in how it runs.


5. When starting the car, it sounds like complete crap.. like rattling pieces of metal under the car (very strange), but after it idles down and warms up (2-3 minutes of idle) that rattle sound is completely gone and sounds 100% normal. I assumed this was the resonator in either an open or closed position, but adjusting that within BimmerLink does nothing. Again, I have about 15 minutes of skill with these two apps, please forgive my ignorance! I apologize in advance if I'm not allowed to do this, I couldn't find any info on posting videos. Here's a video of the rattling noise I'm talking about:
6. The car throws engine codes - at random:
A: 118001: Mixture Control: Mixture too lean
B: 118002: Mixture Control: Mixture too rich
C: 102001: Air mass, plausibility: air mass too high
D: 180001: Catalytic converter: efficiency below limit value

I have both BimmerLink and BimmerCode and usually clear my own codes because it's more of an annoyance than anything. Now, I'm going to guess that when this muffler was replaced, they installed this new air flow sensor and then someone 'tuned' the car for that specific config, hence the reason for the codes above, because I think they are all related. It would be a dream if I could find anyone in the area that knows this stuff to help me tweak this back to the OEM setup without getting completely screwed at the Mini dealer in Cincy.

Here's what I'd like to figure out:

1. Does anyone know anyone in the Dayton / Cincy area that knows / understands tunings and engine configurations within these apps that might be able to help me bring this car back to 100% stock? I'm too old to bother spending time making it .02 seconds faster and would love for it to just be stock and enjoy the ride!
2. If no to #1, is there a way to bring the car back to a 100% stock configuration within BimmerCode?
3. Any ideas on this additional air flow sensor? I don't even know what to test to see which sensor (if either) is even working correctly?
4. Side note: I also seem to be getting another code 8053A5: Invalid encoding data for Equalizing. Not sure what this one is, or if it's related.

I really appreciate any help one could offer. I know I could take this to the dealer, drop 5 grand and get it back to stock, but I'm hoping there's minor things that need done that I can do myself. Thanks for reading!

- Joe

 

Previous owner did some weird things with that car….

Looking at your intake, looks like they removed the air box, which has the MAF mounting location, and just stuck a cone filter in the end of the turbo inlet pipe. And since they removed the MAF sensor mount, they just stuck a new one in the pipe and epoxied it in place. The MAF that is plugged in is probably the one you want to be using.

Reference this site for codes: https://bmwfault.codes
Looks like 8053A5 is related to the active sound generator. Previous owner probably tried turning it off, and coded it wrong? You could possibly get the car coded back to factory fresh, but I’m not sure how outside of a trip to the dealer.