This is totally stock 2008 A6 LS3 Corvette. The owner complaints there is bucking at low TPS situations. It is easily noticeable at coastdown situations.
Now, after googling a bit, it seems to be a common problem with LS3 engines. I took a two scans with just default parameters.
It is interesting to notice that MAF output seems to be very unstable. In the picture below I have changed MAF and RPM scale so it is a bit misleading, but anyway as an example there seems to be huge, +50% change from 5 g/s to 8 g/s, and at the same time RPM varies as well. All this with steady TPS, steady vacuum, steady advance.
Is this something that can be tuned out? Any pointers what to do (you can PM me, PayPal ok)?