It seems like more and more Vanagonites are having this problem more than ever these days.
My 87 Westy with 156K miles has the evil cold start bucking and stalling problem as well.  It
feels like it is running on 3 cylinders and stalls repeatedly.  Once it is warmed up by careful
manipulation of the gas pedal for about 5-10 minutes, all is well-great power, throttle
response, 17 mpg.  Exhaust smells a bit rich, but it has for quite some time.

This is what I have done so far:
Replaced air filter, fuel filter, oil, oil filter, and spark plugs. Found and replaced 2 broken
vacuum lines. Checked throttle switch per Bentley and found it to be ok. I have a nicely
humming idle control valve which was cleaned anyway.  Swapped out the idle stabilizer
control unit with a friends' and got no change in behavior.  Replaced temp 2 sensor last year,
but still need to re-check it.  All this has resulted in no change of cold idle stalling/bucking
behavior.

It seems like the fuel pressure regulator could be suspect, or possibly the "new" temp 2
sensor.  The oxygen sensor doesn't participate in the cold idle loop anyway, so that is
probably not to blame-right? It was replaced about 40K miles ago. My air flow sensor had the
"capacitor fix" when I was hunting down Vanagon syndrome a few years back. Turned out to
be the ECU, which was replaced.

So...I am at a loss for what to do next before giving up and bucking over to my mechanic.
Any last ideas???  I'm not ready to give up just yet!

Thanks, Adam