Sounds a good idea to keep it in tow.

Since you kind of "fixed" everything else, I'd say Bill probably needs to do something with your performance tune. It almost has to be an interaction with your intake and the tune. I wonder if the knock sensor is pulling timing on you at WOT in those RPM ranges? You MIGHT try reducing the timing in the Custom Options menu while in that tune. I'd probably try -1 degree. But, this "reduced" timing will become part of your "previous settings" when you go back to the tow tune, so you'll have to remember to manually change it.

If this works, you could advance it a bit, say to -0.5 and see if things are still good, then to -0.25 if possible.

If this is indeed a fix, Bill could change the timing in your custom tune so you would not have to muck with it.

- Jack