What could cause "rear cyl no combustion" at throttle positions greater than say 70%? Feels like a wicked rich A/F bog, so I tuned my PV the leanest it would let me 70-100% (13.0:1) and still does it. Not a lean hesitation or bucking feeling. I have always had this bog and tried many tunes and changes, but today was the first time I got an "Engine Light" during the bog. Never had it dyno tuned, just butt dyno, midrange and part throttle the thing runs really good but has always fell on its face with bigger throttle openings.