Excellent, you were able to connect and to log. The scope of this thread is intentionally being limited to getting the hardware and software talking to each other and getting the ability to log. Any technical questions regarding analyzing the logged values is beyond the scope of this thread, and this is the last reply I will give regarding your technical questions in this thread. If you have any additional technical questions now that you are able to log, please ask them on www.nefariousmotorsports.com forums, rather than in this this thread, as you are now past the scope of this thread. I am attempting to keep this thread relatively free of the technical jargon, as people don't really need to know the logic behind all of the Motronic ECU just to log their car, and I don't want them to feel overwhelmed by technical jargon.
To address your questions, fr_w and fr2_w (bank 2) are not the lambda values from the oxygen sensors; they are short term fuel trims, and are essentially the same as the frm_w variables mentioned at the bottom of my first post in this thread. They will help you find out that you're running lean because the values are positive (ECU is adding fuel in), but they don't tell you what the what the actual lambda of the car is.
Regarding all of the 'lamXXX' values you logged, those relate to the requested lambda from the ECU, not the actual lambda that the O2 sensors are reading. Those values are all 1 in this log because (according to your RPM, MAF vaues, injection time, etc) you are doing this log at idle, and simply put, your car is requesting a lambda value of 1 at the time of the log. The particular variable that you want to log to see the real, final requested lambda from the ECU is lamsbg_w/lamsbg2_w. The value of these 'lamXXX' variables are not binary (0 or 1), rather they are lambda values that range from 0 to around 1. Like I mentioned above, the RS6 fueling scheme is to stay as close to unity (lambda = 1) as possible (for fuel economy and emissions reasons), and you won't see requested lambda values drop below 1 until your car is enriching when it has a greater load at WOT, or it is enriching for component protection.
To log the actual lambda, you want to look at the O2 voltages that you logged (usvk/usvk2). You then have to know how that voltage correlates to lambda (generally something like this, and pay attention that the X-axis for lambda values for narrowband sensors only span +/- .02):
So with that, I respectfully request that, now that you are able to connect and log, if you have any additional technical questions regarding the logged values, that you head over to www.nefariousmotorsports.com and use the search bar to research any questions you might have about the logged values. And that if, after searching on your own first, you still have technical questions about the logged values, you ask them over on the nefariousmotorsports.com forums or start a new thread here on RS6.com, not in this thread. Thanks!
Thanks!
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