Originally Posted by lug
Since this was only a test there wasn't any need to burn fuel to get to operating temperature. I do mix my fuel with non-ethanol gas along with marine grade Sta-Bil.
That would explain the negative fuel trims. Most new engine calibrations are set for E10, the stoich tables start at 14.08 instead of 14.67. Your calibration is at 14.08 for stoich to compensate for E10. It would actually run better if you use E10. Ethanol is a GOOD thing, not a bad thing.