67 Impala with 5.3 DBW

Have a 67 Impala that another company built. It is had multiple issues. I am down to the finish car and easy deccel even in neutral it loses the throttle body. shut off and restart most times it will have throttle again. A few times had to either wait or I played with harness at throttle body and I had throttle again possibly coincidence. I have messed with air flow numbers all over the place and still don't see where or why. The odd thing is it sets no fault codes except for tach RPM output. normal. According to the what I see in my tune it should set a code air flow mismatch. Compared it to many other cars I have on file and cant see anything standing out. If someone has some insight please. Have went to extreme on air flows and still nothing. ;>{

Here one more little flip. I was backing the car out of the shop. Throttle worked, put it neutral it stopped working, put it in drive Had throttle again, never shutting it off. had wife get in car because we are closing. pull on harness as she is blipping the throttle, no throttle, put in drive and reverse No Throttle again. Shut it off again, start it back up, throttle only in foward or reverse. Not in neutral or park. WTH

Here is another log. In shop getting it to stop having throttle