OK, a Th'giving mystery for you sharp vanagon = sleuths to discern, while I remind myself I really am thankful for my = vanagon!  Here are the facts, as I know them:
I don't see any compelling reason to suspect the = idle control unit or ECU, especially since idle and normal run is good once = warm.  It is only a cold start and cold run problem.  What else could it be?  Could one or more of the components I've tested still be = bad in spite of passing the tests?  e.g., temp 2 sensor would seem a = likely culprit (as some of you have suggested), but could it be bad if it gives = good resistance readings at various coolant (engine) temperatures?  I = would think not.  Hope it's not something more exotic.  I have NOT = done any CO tests (not having the equipment) or output voltage = readings.
 
Any suggestions would be greatly appreciated (and = make my Thanksgiving more thankful!).
 
Jim Creech
87 Westy GL 2.1
79k miles, 2nd owner