Ok guys, I have been chasing my tail figuring this low idle problem and come to find out it only idles low and dies when the brake was pushed. This is manual brake setup no vaccum booster relation.
Anyways , the cuircuit is normally closed until pedal is pushed and opens the circuit for the tcc cuircut to pcm.

So what tables are affected, or affect, when this cuircut is not energized?
I have thought in the past that it was only for unlocking the torque converter but it is definitely related to more than that. I unplugged the pedal switch for this and am going to jump it for now so the converter locks on the highway.

70 chevelle / 2002 6.0 conversion 2bar sd no 02s

Please let me know if anybody can dig up something on this. Searches did nothing but bring up brake booster vacuum leaks which isn't my case.
Thanks,
Mako