Make sure you use dielectric / bulb grease on both ends of spark plug boot ends to stop arcing. Make the plug wires are in-fact in the correct position and fully seated on the plugs and coil pack. Make sure all plugs are still gapped the correct gap, may have moved while installing or not gapped correct at all. Make sure nothing came unconnected like crank sensor or also check knock sensor connection and its working correctly. Make sure all plugs are good using a tester or voltmeter, and same for wires, new does not mean always good not with todays quality control which is no quality control.
Make sure wires are not touching/arcing.
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