Electrical Gremlins -- Related?

[Overpaid Slacker]

The '89 iX has a few gremlins I'm trying to chase down, and I wonder if anyone's had the same issues, and if they're related:

The lights will dim and brighten about every couple of seconds, even at speed (3500 rpm constant) -- both the headlights and the interior/dash lights. It's subtle, but it's there.

The speedo needle will jump occasionally. It'll stay at "true" speed and then hiccup down 5-10 mph, back up a bit and settle back at "true" speed. This happens w/o regard to the dimming of the lights.

Most strangely, I reset the oil change lights a couple of weeks ago, and deliberately reset the inspection at that time (though it wasn't on). The inspection light just came on a couple of days ago.

The time/date "computer" will sometimes be bright, sometimes dim and sometimes change its luminosity depending on whether the headlights are switched on; but likelier than not, it changes to "bright" when the headlights are switched on, which seems backwards to me.

If you start the car w/ the headlight switch fully on, the headlights won't work. You've got to shut the car off, turn the headlight switch off and restart the car. Only after the car's been restarted can you turn the headlights on.

I've had the alternator checked and it and the diodes appear to be fine.

Anybody got any theories? I'm thinking I need an old priest and a young priest.

JP

[Jared at Pelican Parts]

Did you check the voltage regulator?

[Overpaid Slacker]

Jared -
I have not personally, but I asked my wrench to do it when I had the injectors changed a few weeks back and he said it spec'd OK.

Could it be the headlight switch causing the majority of the problems?

JP