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93 Explorer gets an ignition miss after its warmed up

152000 miles. Religious oil changes at 3000 miles. New plugs before this started.
Drove about 60 miles on a warm day. Ran fine. Went to start it again, it seemed to be running on only 5 of 6 cylinders. Carefully limped it home. It did not overheat (stayed at normal temp) and the engine never died.
The next day I pulled each spark plug and had a look. They all looked fine, none looked fouled. The dead cylinder was not obvious. Started it up, it ran great. This was an even hotter day, drove off to do errands. Probably drove 5 miles. Stopped, and when I started it up again, the miss was back! Went home, and while it was still running crummy, tried running it with one plug disconnected from the coilpack at a time, until I found the one that it didn’t seem to matter if it was connected or not… cylinder #2. Later pulled that plug again, fine. Plug wire measure about 5K ohms on my meter, as its the shortest one. Sounds about right to me.

Today (its about 75 degrees) I bought a new coil pack and put it in. Ran beautifully. Warmed the car up, still ran nice. drove a few miles down to the freeway, ran great, got off at next exit. Proceed to run just perfect until I was slowing down for a light, then the miss came back. UGH!!!

Beyond checking the compression, what else might I try? I don’t tolerate mechanics BTW, I do everything myself.

Thanks,
dyno

Also, forgot to mention… no Check Engine light ever comes on. This car is pre-OBDII btw.
thanks,
dyno

The miss might be caused from a fuel injector ready to give up the ghost. Try swapping the fuel injector from cylinder two with another fuel injector on the engine. If the miss moves with the fuel injector to that cylinder that pretty much confirms the fuel injector is the problem.

Tester

That would require pulling the upper manifold TWICE.

Silly suggestion maybe because you probably tried this already but could you switch two of these new plugs around so see if it follows the plug?
Since it started after you replaced plugs, maybe one has some sort of weird intermittent problem…