It took me awhile, but I finally broke it..
Hardly an indication, just reliable reliable and then poit narf egad dead.
Let's start from point a: cold, a bit hesitant. Blamed on darn darn cold. Still, a sufficient warmup time.
Get gas. Start car, pull up to lot for a soda.
Car will not start. Get jumpstart
Car runs. Proceed toward home, but now getting crazy voltage readings. 18v, turn on something,
drop to 12, then back.
At this point I'm in semi-panic mode The car decides to go for a full panic,
and I lose power. Nothing to do but navigate to the side of the road, ponder.
It being 19 and dropping, I kind of had a notion i was toast, so I got a ride and a tow.
Believe me I've done worse and it's still in my yard to remind me of my incompetence. I don't learn.
Okay, I learned to get a tow rather than drive with no coolant. Different story.
Post-tow, at somewhat normal above-freezing temps (40-50)
Battery: dead. Replaced with newer, but not new battery, charged. Cranks,
Still no start.
All dash fuses except charging have battery voltage.
Swapped out a disty rotor cap with no change. Removed anti-diesel valve pin. No change.
3.4v at fuel pump droping to nil.
Not checked yet:
Fuel pump control unit
Those other half dozen circuits in the dash.
Materials on hand:
Spare distributor, alternator
Complete system on hatchback (which will run when presented with gasoline)
Odd phenomenons, which might be blamed on the low battery of the time:
during restart attempts
tach jumping, entire system dissapearing from ignition circuit at times (but at that point the battery was showing about 6-7v on the gauge.
Odd things like a brake fluid warning light when there is sufficient fluid. And then off. On.
The 18v cascaded through the systems and fried a component or two.
That the alternator voltage regulator is not regulating (but the very dead battery might have caused the high volts, dunno)
Signal not getting from dist to fuel pump relay
The jump start went wrong somehow.
TLDR: near- dead battery caused charging system to go out of spec, causing something to break that didn't get fixed with a fresh battery. Trying to find the part to repair.