What I have discovered  is going down large hills with the
engine being overrun by the wheels, the engine gets maximum
cooling and produces no engine heat.  This in turn cools the
engine to the point that the ECU thinks the engine is hotter
than it really is.  The engine then gets a little to lean
fuel/airmixture,  for a few moments, causing the stalling.
    A simple fix is to throw in the clutch and drift, with the
engine idling.  CAUSTION drifting like this is against the
law in some state.   Who knows why...
                                                        Eric

Steve Selin wrote:

> This happens to my friend's 1987 Westy all the time after long downhills
> going through towns - once it has been cruising on the highway for several
> hours.  It is VERY predictable, but no-one around here can figure out what's
> up.  Any new ideas?  Often it doesn't actually die, but just putters like a
> clogged fuel filter - but the filter is not it.
>
> Thanks,
> Steve
>
> > There was one thing that happened about two hundred miles from home on
> > our return... After a long decent, I went to accelerate and there was no
> > power. It felt like the engine died, but no engine lights came on
> > (perhaps they don't on Vanagons). After slowing a bit, I down shifted to
> > see if I could get her to start up. Still nothing. Took her out of gear
> > and coasted to a stop. Turned the ignition off, then on. She started
> > right up. Put her in gear and started rolling but by the time I got her
> > in 3rd, she was hesitating, lost power and died again. This happened 3
> > times. On the forth attempt, success! She started up and ran like
> > nothing ever happened and got up home. <<<
>
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