Cold solder joints in the computer.  I just fixed one with
the exact same problem.

            Eric                   86-VW4x4
            vw4x4@fyi.net          86-SS Syncro
            Pittsburgh, PA USA     1936-Chrysler
                                   92-Jetta GWC
            www.fyi.net/~vw4x4/vw4x4.htm

On Wed, 29 Sep 2004, Jim Felder wrote:

> This is an inquiry about a vanagon that's not mine. There's a guy
> around town who works as a handyman. He bought a vanagon--it appears to
> be an 87--for $400 at goodwill. It has run fine until now. He knows I
> have two, and he sees me around town, and he stopped me today to ask if
> I knew what was wrong with his. He knows very little about cars in
> general, nothing about VWs, and doesn't have the money to take it to a
> shop and get it diagnosed.
>
> Here's what he's told me: the car runs OK cold and warm, but quits when
> it gets hot until it cools off. He's been told it's a sensor in the
> distributor (hall effect is the only one I know of) by one of his
> friends but I suspect the coil. I had a coil once that had a break in
> it. The coil would expand under the effects of heat and thus open the
> break. Cooling would allow the broken wires to contact each other and
> then it would work again until it got hot.
>
> One clue from him is that it ran very rough prior to the first time it
> cut out, making him think it was a clogged fuel filter or bad fuel
> pump.
>
> I asked him to see if he could check the coil, but also told him I'd
> ask on this list. Of all the things I've done to a vanagon, ignition
> troubleshooting has not been one of them, so any help would be
> appreciated.
>
> Thanks,
>
> Jim
>