Running on three cylinders....

[Thing7]

Started up my trusty Thing today and noticed it felt like it was running on three cylinders. In the past this has happened a couple times and it was a plug wire that popped off the plug. I have new wires and checked them all and they were secure. Started popping wires of the distributor and located the one that didn't affect the engine when I removed it. Pulled the plug and checked for spark and had spark. I'm not sure where to go from here. Any suggestions?

[Thing7]

Update...Half hour later I start it up and it feels like it's running on all four. Start driving and she's running strong...for about a block and then back to running like she's on three

[Thing7]

Updates and still not sure what's going on.

I started with cleaning the distributor cap, rotor and points which were kind of dirty. After doing so it was running on all four. Maybe just a coincidence because after driving for a while I would get some sort of miss or hesitation while driving. When I'm sitting still and rev the engine it sounds super strong and doesn't miss or hesitate.

This weekend I discovered that when I first start driving, the engine is fine and strong with no hesitation. But after about 10 minutes or so when it heats up I start getting bad miss or hesitation under acceleration. Another weird thing is that after driving for 45 minutes, I stopped for about 15 minutes and when I got back in and started driving, there was no miss or hesitation under acceleration...but only for a mile or so and then it was back.

So... A few things that I'm wondering if could be the cause and wanted to know if anyone has any thoughts. One thing to keep in mind is my initial post when I started my Thing and it clearly felt like it was running on three cylinders just sitting still. After pulling each distributor wire and having each one make the engine run worse until I got to cylinder four. But as mentioned above, the engine now runs strong at idle and at revs while standing still and the hesitation is only under load and acceleration.

1. Could a badly adjusted valve cause the miss or hesitation while under acceleration but not present itself while sitting still and revving?

2. Possible the plug in cylinder four which I thought was the issue and checked for spark maybe has spark but not enough. Was thinking to start by changing plugs.

3. Carburator issue? If it was the carb, would it still run perfect while sitting still and revving and only present a hesitation under driving acceleration?

4. Possible distributor, roto, points?? Same question as above. Would it still run fine at idle and revving but present hesitation only while driving?