I had a similar problem with my '84 GL.  In my case it Turned out to be
vaccum leaks.

I replaced all the little hoses and also found a tear in one of the
folds of the throttle body rubber boot (had to remove it to find it).

Two of the unexpected culprits were  1.  The oil filler tube (the
plastic part was not sealing against the metal pipe) and   2.  The seal
where the dipstick tube enters the engine case.

Of course you know Vanagons .... (The ankle bone is connected to the
foot bone) .... any number of things "In the loop" that are out of whack
can give the same end result (symptoms).

Mike
'84 GL Mongo

----- Original Message -----
From: <JordanVw@AOL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, April 02, 2002 10:54 AM
Subject: 1.9L bogging down on acceleration when hot..anyone ideas???

> when i drive my '84 1.9L wbx for a while, then stop at a light and
idle for a
> few mins, then pull out again, there is no response at first when i
step on
> the gas, it bogs down and then finally starts moving when the guy
behind me
> is almost up in my rear bumper..  any ideas?  i've been adjusting the
idle
> speed screw, it doesnt help.
>
> Thanks in advance-