I dunno much about the WBX motors or automatic vanagons but your symptoms
sound like it gets a Vapor Lock....It sounds like you are getting heat into
the fuel system somehow causing the fuel system to deliver air rather than
fuel.
   Are you certain your temperatures are correct?   A faulty ground can
cause your coolant temp gauge to read really low.   230 oil temp IS quite
warm...right at the top of where you want to see it go no higher....
   If any of your fuel lines run near a heat source or perhap the fuel rail
is missing some heat shielding?

 Another lesser possibility is the coil...Sometimes they get wonky when
they're really hot and they are on the point of failing....I might go there
first, even if you recently put a new one in....New one have been known to
come faulty...
  Don Hanson

On Fri, Aug 17, 2012 at 1:29 PM, Rocket J Squirrel <
camping.elliott@gmail.com> wrote:

> ADDITIONAL BIT 0' INFORMATION: Though we were climbing up very steep,
> long grades in 90F+ (over 100F on one day) temperatures, at no time did
> the engine register too hot. Oil temp was below 230F, temp gauge barely
> made it to the right of the LED.
>
> --
> Jack "Rocket j Squirrel" Elliott
> 1984 Westfalia, auto trans,
> Bend, Ore.
>