That sounds like the typical hot weather symptom for going from high load
high rpm driving to idle. But yours came on while still driving on the
hwy?  Somebody who knows the system better may have more info about what
circuit to check to see if it might be a bad connection.  Safe travels!
Edward

On Tue, Jul 19, 2022 at 8:18 AM Mark Pinnell <mark.stuart.pinnell@gmail.com>
wrote:

> Hi. Oil level was fine this morning. Started it, and all seemed good.
> Couple miles on a service road, then a secondary highway, now have been
> back on 20 east for 50 miles with no issues (yet?).
> The oil light has flickered at low idle for the 12 years and 100000 miles
> that we have had her.
> Thanks,
> Mark
>
> ---------- Forwarded message ---------
> From: Tom C <thomas.casal@gmail.com>
> Date: Tue, Jul 19, 2022, 6:40 AM
> Subject: Re: Oil Light On
> To: Mark Pinnell <mark.stuart.pinnell@gmail.com>
> Cc: <vanagon@gerry.vanagon.com>
>
>
> Mine flickered for a second yesterday  on a 6 hour ride on a highway ramp,
> I hit some bumps real hard not sure if that Jarred the wires. I was pushing
> it too a bit at 75 for a while gowesty 2.3 motor in an 84. I’m Interested
> in what people have to say too now. I may be a quart low tho gotta check it
> today not sure if that has anything to do with it.
>
> On Mon, Jul 18, 2022 at 11:41 PM Mark Pinnell <
> mark.stuart.pinnell@gmail.com>
> wrote:
>
> > Hi all,
> > Just made a very quick exit from Hwy 20, just east of Montreal as my oil
> > light came on, solid. Just over 400 miles covered today.
> > 1985 1.9l  Oil level appears to be OK, no different smells out of the
> > engine bay, and no noticeable difference in engine sound or performance
> > (I'm using that term loosely).
> > It's slashing down rain, as it has been all day. Luckily, we're in a
> > service station, so we can bed down for the night and see what the
> morning
> > brings.
> > Interested in any thoughts that the group may have as to what the cause
> may
> > be, possible diagnostics, etc..
> > Mark
> >
>