So I hunkered down a couple nights in Minot and in Bismarck now. 98 degrees, I am in a hotel.
My van developed a misfire and coil DTC Sat at the end of the day with dash light. My reader only provides codes and I didn't know what cylinder. After resting 15 minutes, it was fine. I mistakenly cleared the codes, but did note them.
The next day I bought an Autel code reader.
Drove to Minot Mon morning with no problem. That afternoon in high heat at a stop light I got a bad misfire and flashing lights. New code reader picked up the misfire and coil problem on cylinder 5. All 8 coils are new with 3000 miles.
I carry an extra coil that I used to replace the problem one yesterday morning in the hotel parking lot. Test drives were good. Today in high heat with same circumstances all seems good.
I now have a couple new coils.