Long and Short Term Fuel Trims (LTFT & STFT) in OBD2

[dziacial]

Im trying to check STFT and LTFT in my GLK350 from 2010 with OBD2 scaners. So far I wasn't able to do it.

What I tested:
1. ELM327 with Torque app - I can display real time values but they are very random, changing all the time and quite large. LTFT should me more stable not changine every second.
2. AutoCom from Delphi - there are two modes. In one I LTFT and STFT are unavalible. I the other I can display the same values as in Torque
3. One other OBD2 scanner without name - the same value as in Torque but there is an option to divide them by 4 and after this it looks a little bit more like real trim values.

The result is I cannot find values for LTFT and STFT in my Mercedes OBD2 or they looks nothing like in other cars.

(Values for O2 sensors I can read without problems.)

I also tried Xentry with VXDIAG SE and there are values for "Selfadaptation in idle speed range" what looks and behaves like LTFT. I also found the same values in Vediamo but thats all.

Does anyone know how to reliably read real time values for LTFT and STFT in GLK350 with M272 engine or is it possible that ECU (EM9.7) for this engine doesn't use this values to adapt mixture.

 

[dziacial]

You can check how STFT and LTFT values in my car changes here:

 

[alexanderfoti]

I have noticed that via OBD the LTFT values are a repesentation of the adaption values at that rev range.

If engine is idling then it's the idle trims.
At 2500rpm it shows the mid load trims.