So I bought at 1993 hatch civic with a d16z6 that smoked terribly, so I got a d15b7 and did the mini swap. It ran perfect and then I changed the old plugs bc I fogot to do that and now its misfiring cylinder 4 and a small valve tick that goes away at 3k and up. Can someone please help me or give any advice with this issue? I would be very thankful