I have a 2003 with 171xxx currently. Bought it at 169xxx. My dd. Bought it in December. Since then I've changed the spark plugs with NGK IR. The ones it came with looked like the original for the car...They were horrible. K&N fipk intake. Tanabe concept g exhaust. Invidia TP. Changed the PCV valve. I changed the oil with with valvoline max life high mileage 10w-30 and have to keep adding oil since ap1s apparently consume it, but I was also leaking from the vtec solenoid but I've changed those gaskets and that leak is gone. Before changing the exhaust my rear bumper was always covered in soot. I was told that was blow by. My problem now is, since putting the exhaust on there I blow smoke like crazy now. It has a burning smell to it. Sometimes a blue tint to it. Mostly a darker color but also sometimes a whitish.... it smells bad but I know that's from the test pipe. When I take off from a stop it lets out a little plume of smoke. Pretty embarrassing and I hate it. I checked my sparks plugs today. Cylinder 4 (closest to the firewall) it covered in carbon and oxidation as seen in the picture. The other three had light carbon build up at the base of the threads. They all had a little oil residue under the washer. The car runs fine, pulls hard, I've never had a problem in the few months I've had it. judging by the picture smoke billowing out of it what kind of options/advice/fixes can you guys give me? any insight is appreciated.