Swap the cyl.5 coil with cyl.4 and the cyl.5 spark plug with cyl.6. Clear the fault data and drive it. This will narrow it down to the following:
1. If the code for misfire moves to cyl.6 then it's plug related.
2. If the code for misfire moves to cyl.4 then it's coil related.
3. If the code for misfire stays at cyl.4 then you're down the rabbit hole of checking wiring/connector plug
/CU/mechanical fault in cyl.
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