I may have to eat my words. I found some suggestions on not dropping the AFR after it gets to 13 at higher throttle levels. I'm going to try some maps that level it off to 13.2 around that 59% throttle. Also look in to a clean fuel filter, air leaks on the exhaust, possible leaking fuel line in the tank.

 

The last couple of days I have seen a lot of good results with leveling off the afr at 13.2 at higher throttle positions. What base map are you using?