FireMan

Just got done taking apart and cleaning my throttle body, adjusted perfectly the TPS, and did a 90% electrical and vacume check on my 3.0 I am having problems when after the engine has been running higher than normal idle (800 rpm out of gear) that my idle is low, around 550-650. If I was in gear, (automatic) the engine practically wants to stall out. I'll I have to do is while sitting at a stop, lightly "tap" the gas, and it regains a perfect idle goes until the next stop. Then I have to repeat the "tap". Drive some more, come to a stop, idle drops, "tap", ect. It dosn't have the symptoms of a bad TPS with the engine rpm being high or wandering. The TPS checks out electrically muy bueno.

I can reproduce this in my driveway, and by hand, "tap" the throttle linkage and the idle is good again. Now my questions:

Are the throttle return springs pulling too much? They are original.
-or-
Do I have a sticking throttle/criuse/transmission kickdown cable?
Is this preventing me from correctly setting the TPS, and idle, and timming? Then when the calbes finnally let the throttle return to fully closed, the idle screw is not set for the REAL closed angle but the one where the butterfly valve is partially open?
-or-
A leaking butterfly valve?

I think I could reset the main throttle stop screw to compensate for the leftover play that seems to casue my idle to drop so much, and recalibrate the TPS, but then the butterfly would be open out of spec. As far as I can tell. Everything else seems to be in spec and run perfect, but it is really annoying to constantly be "tapping" the gas all the time.

As far as the FSM and my knowledge so far had led me to believe, the throttle body is not something you would normally alter or fix other than boring it out.

I belive the throttle body and its linkages are the culprit becasue I can always simulate and "fix" the problem with the observations noted above.
Any ideas? Thanks!