I've got an older silverado with a swapped 2007'ish 5.3L with 4L60E attached. The truck seems to start in second even when flooring the gas, and will shift into 3rd & 4th fine. But while in "OD" it will not start in 1st gear, or downshift at all when applying throttle. I can force it to downshift manually with the shifter on the column, but it won't do it on it's own.
Can someone give me a sanity check on this tune and make sure I'm not missing anything? I've disabled all the TPS fault stuff that might cause an issue. Any help would be appreciated.