Cause
Coil insulation breaking down when hot
An ignition coil whose internal insulation has degraded, breaking down under heat and load so the spark finds an easier path to earth than the plug gap. The coil works cold and fails hot, which is the whole of its diagnostic character.
So the complaint is a misfire that appears after twenty minutes and disappears overnight. The vehicle arrives running perfectly, every static test passes, and the resistance measurements are within specification — because resistance measured cold says nothing about insulation that fails at operating temperature under thousands of volts.
Load and heat are needed to reproduce it, so testing at idle in a cool workshop will not. A visible crack or tracking marks on the coil body confirm it — look for a thin carbonised line down the insulator. Oil in the plug well accelerates it by attacking the boot, so check the well before fitting a replacement, since a new coil into an oily well fails the same way.
Typically an easy fix. Often worth checking before paying anyone to look.
Some of these codes mean you should stop driving
2 of the 2 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (2)
Codes where this is a likely explanation first, rather than merely a possible one.
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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