Sometimes, randomly, my truck won't crank...one time we played with the neutral safety switch and it cranked. The next time that didn't work so he unplugged/plugged in the starter fuse and it cranked
Your starter may be on it's way out. Next time you have the no start issue, have someone hold the key to the ON position while you rap the starter with a hammer. If she pops over, you need to replace the starter. May have just been a coincidence that it happened to start those other times.
https://www.youtube.com/watch?v=fpPOcO6f798 You can do these tests with the starter in the vehicle. Does not have to be on a bench.
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