After a lot of help from Chris (trekster) I think I'm starting to understand how this is all working. I looked at my settings for the wideband and it only allows the wideband to make corrections to the AFR up to 135kPa MAP. After that point, the TEC3 relies on the predefined values in the Volumetric Efficiency table. Even when the TEC3 uses the data from the wideband, it has an authority range of 2%. I don't know if that is a 2% change in AFR or 2% change of the values in the VE table. This would explain why my AFR of 12.5 didn't get adjusted to 12.0 at full boost.ISJeff said:I'm not sure how much adjusting it does though. I was hitting 12.5 AFR under boost, but if the wideband was really being considered it should have adjusted the AFR to 12.0. I'm not an expert on the TEC3, but I thought it would correct something like that.