No it's not normal.
Can you swap plugs and see if the misfire moves.
I can't remember what I gaped my plugs at. But I don't think it was that small.
228,000miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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