I'm glad you ask that...
A while back, I made a new post regarding datalogging but none seems to care about it, even though datalogging is the most important part of having a realiable powerful engine and the only way to tell if your chiptuner has done all his job correctly.
For MED17 VCDS still can't datalog groups, only single chanel logs, you can select several ones though.
If I were you, I'd datalog timing retard for all four cylinders, AFR, ignition timing, maf readings, intake temps vs RPM and load.
Let me know where would you like to start and what you want to datalog first and I'll help you out.
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