When I read your other post yesterday, I was going to suggest disconnecting the kick-down, but after reading all the testing and diagnosis you did, I didn't want to be insulting. There's some lessons here, I think.
One is something I've finally learned, about that 'desperation' that sets in after a problem surfaces, you chase all the possible causes, assuming the worst case scenario, and end up overlooking the simple stuff.
I couldn't begin to relate how many times I went all-out to 'cure' something that was embarassingly easy to fix, had I only stopped and made it a point to first check the simple answer first. Trouble is, only experience seems to drive the lesson home.
I remember an old 450SE that I changed the brake pads and rotors on. After proudly buttoning everything up, the pedal went to the floor. I re-bled a 1/2 dozen times, then finally concluded the caliper(s) or master cylinder must be bad. So I changed them too. After several more bleeds and some road testing, the brakes worked fine. Only many years later did I learn that they take awhile to seat in, and the initial spongy feel is normal.
I remember..well, you get the idea. Now, I always take the time to search out what the simple causes are likely to be, before launching a major project to change anything. The saving grace is that we do gain knowledge and experience from doing even the most futile things.
So, when that 'desperation' sets in, I try to let that be my signal that I may have failed to see the tree for the forest. Glad this worked out in the end
