Sure sounds like a fuel pump problem to me.  Pop one in for about $150
from one of the list vendors.  Or, you can get a pressure gauge and
measure the pressure when it acts up and see if it is in spec or not.

Doran Nugent wrote:
>
> I was driving from Massachusetts to Seattle when
> around South Dakota the 1990 Vanagon Automatic started
> losing power intermittently as if running out of gas
> momentarily then coming back on. This happened over
> and over every few seconds to few minutes. It would
> slow from 65 MPH down to about 30 MPH then would start
> revving again. It was very cold at the time but that
> may have been coincidental because the symptom
> continued when the weather warmed to above freezing.
>
> Also, by applying full throttle the problem was
> exacerbated. To get the engine to come back, I had to
> ease up on the throttle until the engine decided to
> come back to life then I could speed up again.
>
> A similar condition in a different vehicle was
> remedied by adding "HEET" to the gas but it did not
> work this time.
>
> Now I am in Seattle where the weather is temperate and
> the problem seems to have gone away for the most part.
> It still happens, though rarely. I'd like to know the
> cause and how I could prevent it from happening
> again...Any ideas? Thanks in advance.
>
> Doran '90 Weekender as yet unnamed.
>
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--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

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