Quote Originally Posted by Aceshigh View Post
You're getting into territory that I'm not familiar with. IIRC the ratio should be closer to 13.5-14.5 so this looks like you're running really rich. The multiple misfires might be telling you that the car is not running on all cylinders. If you are dropping cylinders you might be increasing unburned fuel and that might be causing your AF ratio to go so rich. This is all specualtion and you need to find a shop that knows what they are doing because it seems like you're on the road to a bad failure. (I'm not saying Will doesn't know but you need to get it back to him if he does)
dont go anywhere near 13.5 under WOT on a turbo vehicle. 12.5 is getting a little lean. The multiple misfires may be due to spark blowout, meaning your plugs are gapped too wide. .32 is what alot of turbod cars use.

OR your plug(s) could have closed shut from boost.