General Low fuel trim stuck at 100%

[Echo5Zulu]

Had the resistors melt down in an ECU so I threw in one out of my donor car that has been in my dad's barn for about a decade. Opened it up and looks like the resistors have been replaced already so I threw it in. Having a hard time getting it to idle at all. Put about three hours or more into tuning and driving and mid and high trims are moving and getting set in nicely but the low trim won't ever move from 100%. Usually low is the first to move but this one won't. Wideband says it is running lean at idle, but I have maxed out the safc at that rpm. I also have 1200cc injectors, running 42psi fuel pressure, and on E85. The car idled perfectly w the old ECU. Could there be something wrong w this ECU that just effects the low trim? Anyone see this behavior before?

 

[Echo5Zulu]

Had the resistors melt down in an ECU so I threw in one out of my donor car that has been in my dad's barn for about a decade. Opened it up and looks like the resistors have been replaced already so I threw it in. Having a hard time getting it to idle at all. Put about three hours or more into tuning and driving and mid and high trims are moving and getting set in nicely but the low trim won't ever move from 100%. Usually low is the first to move but this one won't. Wideband says it is running lean at idle, but I have maxed out the safc at that rpm. I also have 1200cc injectors, running 42psi fuel pressure, and on E85. The car idled perfectly w the old ECU. Could there be something wrong w this ECU that just effects the low trim? Anyone see this behavior before?

Thoughts anyone? Bad ECU?