My fuel trims are as follows:
High(#0E) = ~0
Mid(#0D) = ~-2
Low(#0C) = ~-12.8

From the ecuEdit XML: (128-[value])*0.2 <---Is that correct?

The Mid and Low move around a bit but the values listed above are where they "hang out". What could be causing the -12.8 Fuel Trim Low? I have stock injectors, intake and BOV. The car is running fine but does the occasional stoic -> lean -> stoic during idle.

I don't think the BISS is where it was when it left the factory. I'm not sure if it's in or out from the factory condition. I understand how this could cause the stumbling AFR during accessory switching at idle... but how does/could it affect the idle fuel trim?

Thanks in advance!

 

Come on guys.... help me out a little here....