Driving along at 70 mph on a highway and this happens. Had to be something simple but standing on the side of the road without any tools means call for a flatbed.

got it home, pop the hood, check the cap and rotor and what did I find?

one of the screws worked itself out and started bouncing around inside the cap

Next time put a drop of lock-tite on the screws

Nice sleuthing Sherlock...!!!  Glad that the issue was something simple to remedy.

And thanks for sharing...!!!

I have seen that happen before....never at a good time, either. Harmonic vibrations can cause those screws to loosen. Crankshaft/oil pump/flywheel vibrations can be transferred from the cam to the distributor thru the timing chain. Of course, the screws could have just been left a little loose, too. Glad it wasn't any worse than it was!

Last year I was on a ride with our Corvette club and all of a sudden the engine was backfiring back up through the throttle body.  It would barely run, so after getting home on a rollback and pulling the valve covers, I found that one of the exhaust rocker arms had broken.  So that cylinder would fire, and with no place for the hot gasses to go, they blew back into the intake when the intake valve opened.  If it had been an intake valve it would have just been a misfire. I replaced all the pushrods and the rocker arms with roller rocker arms -- I didn't want to go through that again!

One issue with the roller rocker arms is that they are taller, and required tall valve covers, which meant modifying the mounts and belts for the air conditioner compressor and alternator.

Pleased that it was something simple.

Last year our '78 suddenly refused to "pull", having done a 70 mile drive to an event venue without any issues.   Then when we left to drive to our hotel it would hardly run.     We had taken only a limited selection of tools, but I did manage to remove the distributor cap and check that all out, to no avail!

It turned out that the coil was the culprit, but I didn't settle on that diagnosis until it was too late in the day to order a replacement.  So, a day wasted at the hotel and a  VERY expensive ride home on a flat bed ensued.  (We discovered that the breakdown assistance here in France is woeful compared to the excellent service in the UK!)   I ordered a coil from the parts chap I have to use here now, over in Alsace, and it arrived the next morning.  If I had realised, I could have had it sent to the hotel and swapped it in the car park!

The episode has taught me to keep a few more spares in the car at all times and, carry a more decent set of tools! 😄    

Similar problem 15 years ago when I first got the Vette running. On the way home from a party, showing off my new toy, the car starting bucking half way home. Maybe 50 miles on it at the time. Definitely an ignition problem I said to myself, but wait!! All the parts were new from spark plug/wires/coil and distributor.  Made it home but scared the wife into not riding in the car again. To this day even.....

Turned out the ignition parts inside the distributor were not good ones, a second set of points/condensor did the same thing after changing them AGAIN after 100 miles.

Change them 3rd time, now using original OEM GM parts. Problem solved. I believe the problem was the condensor only, breaking down under load. Name brand part but really auto part store junk.  😁

Not specifically a Vette issue, but years ago my father in law had me drive a Mustang he had worked on.  About 5 miles from the house it shut off like the key was turned off.  I pulled the distributor cap and everything looked normal.  I hitched a ride home and later he got the car home and fixed it.  I asked what the issue was; all he did was replace the rotor.  The old one looked fine, no cracks or anything that we could see, but there was a gremlin in that part somewhere.

Hit it back together this morning with a new cap, rotor, and points. I put a though of lock-tight on the threads so hopefully that won’t happen again.

i can’t remember the last time I changed the points but I do check the dwell every spring. They didn’t look bad but was time anyway. 

What about eliminating the points and convert to a Pertronics or MSD ignition?

AMEN! Did it many years ago. Best decision for ignition in my book. Can't beat it. Starts first time, every time.