View Single Post
      03-21-2017, 03:40 PM   #11
MysticRob
Captain
MysticRob's Avatar
573
Rep
870
Posts

Drives: 2009 335i E90
Join Date: Jan 2017
Location: Fremont, CA

iTrader: (0)

Garage List
Quote:
Originally Posted by Jeff@TopGearSolutions View Post
I did do some logging a few months back. I plan to re-visit the idea again. I believe when I did the logging I could not find anything distinctly wrong but I may have not gotten a good datalog on the issue cause although I can duplicate it, sometimes when in traffic it's hard to do it. I usually need a good long even straight with the light throttle and even consistent road to get it to do it. I think that's why I haven't done much more with regards to finding a solution.

I know for sure one thing temporarily fixes the issue, resetting adaptations. After I reset the adaptations it won't come back for a few days or even a little over a week and of course adding more throttle helps too.

Also it did get a lot better when I opened up the intake manifold fitting to a 1/4inch size for the Tial BOV.
Interesting. What happens if you reset only 1 adaptation at a time? I'm curious if just resetting the lambda adaptations might cause any changes. Could help point to a problem with that specific sensor(s).
Faulty O2 sensors have been known to cause RPM oscillations before so might be worth a try.

I'm also curious if changing things in the MHD tune, like throttle mapping, Stage 1 to 2, etc, resets all the adaptations or not too.
Appreciate 0