Thanks everyone.  I think Stuart hit it (fingers crossed) with the idle
control module.  Swapped in one I found in the box with me spare ECU that I
have had 'forever '.  Drove a hundred miles with a few long descents
without any signs of engine dying..
   I'd never have found my problem with out the List...heck, I didn't even
know there was such a thing as an idle control module...the one in my
spares was labeled "ign. Control mod. ". I recall, vaguely, the fellow at
German auto salvage, in Boring, Ore. asking me if I wanted that part,
too...and tossing it in for nothing with the 91 jetta ecu that was
$35...about 5yrs ago.

On Fri, Sep 14, 2018, 11:12 AM David Beierl <dbeierl@attglobal.net> wrote:

> >
> > The injectors shut off when going downhill and rpms are above 1200. As
> > soon as rpm drops back down to 1200 rpm, the injectors fire again
> >
>
> With Digijet I believe the cutoff is at 1500 rpm and fuel comes back on at
> 1000 rpm. It's a little more complicated with Digifant. The engine has to
> have achieved 3,000 rpm before decel mode can be invoked,** and I think it
> comes back on at 1300 rpm.
>
> **I believe this is since the last time the closed-throttle switch was
> active.  I did tests on this once but don't remember the exact results I
> got.
>
> Yrs,
> d
>