Code P 1339?
It MAY be a random/multiple cylinder misfire, according to the Honda Civic online forums. I'd have a mechanic or service tech @ Dealer double check to be sure.
Is that the only code? Nothing along the line of P0300, P0301, etc? P1339 is random misfire, check all your plugs, plug wires, ignition coil, rotor, etc. Pull your plugs and check their condition.
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