Odd starting problem

Today when I came out of Church to drive home, my 83 would turn over like 2 times (rrrrr-rrrrr) then stop abruptly. It sounded like it normally does when starting (same speed, strength etc.) but it immediately stops after a couple of cranks.

I tried it a say 3-4 times. Always just a couple of turnovers then immediate stop. Then I went to the back and took all my guitar equipment out of the back, wiggled the battery ground strap a little, tried it again, started like normal. Ok maybe something loose etc.

Later that day, I rinsed off the car (pulled out of the garage first, no issue starting) and afterwards took it for a spirited short drive to dry it off. Came back and cleaned the windows, then tried to put it back into the garage and bingo! Exactly the same thing happened. A couple of spirited turns then an immediate stop.

Turned it off, tried it again...started right up no issue.

I have looked around here and RL but don't really see the same symptoms. I have not tested anything yet. Although it seems as though the volts were not particularly high today. Normally, just below 13 is very good, but sometimes it hovers near 12.3-5 more often than not. So I know I need to check some things. I am not up on electrical troubleshooting though so I am just wondering if this strikes a bell with anyone.

I would suspect to test the volts on the battery posts first and the ground strap and go on from there including the involved relays and fuses, then finally to the solenoid, starter switch etc. as needed. I found a couple of articles about some of those things so I will start there.

Will let you know if I find out anything. I am suspecting electrical gremlins.

Could just be a loose ground or weak battery, when you get to the end of a compression stroke, the resistance is just too much.

It sounds like you had plenty of battery each time. No clicking noises???

Sounds more along the lines of a tired, old starter motor on its last leg to me.

Tired starter motor or more than likely a corroded ground strap and or other corroded ground points. Clean all grounds and replace the ground strap and I bet your problems disappear.

Thankfully when I came out of church this AM with all my guitar gear I didn't have that problem! Hope I never do, but frankly it is only a matter of time!

Thinking the same as James.

My 928 S4 has just decided that it wont start unless I pump the throttle like a maniac any Ideas?
Just to baffle me even more doing 30mph yesterday and lost all power it just decided to cut out are these 2 things connected.
Stumped!