Carbon tracking is usually caused by oil, dirt, or moisture, creating a path to ground another symptom well. It’s a severely eroded spark plug electrode that will increase the firing voltages to the point that the spark will seek the point of least resistance, which is either through the spark plug boot or down the ceramic insulator of the boot on the coil. If carbon tracking is found on a spark plug or coil tower, an identical track will also be found inside the spark plug boot. If the misfire has been ongoing, the boot could show signs of cracking.
If the boot or wire set shows signs of flash over, the boots and wire set should be replaced along with the spark plugs.
Failure to change the components together will result in the carbon tract transferring from the old components to the new components over time. By just replacing the spark plugs or ignition wires, the problem may be temporarily solved, but after some driving, the probably right back and the components will all have carbon tracking on them. This is one reason that it is always important to replace all the secondary ignition components at the same time. It is also important to look at the seals in the valve cover that seal the spark plug tubes.
If the well is filled with oil well, it could be causing your carbon tracking to prevent a comeback.
Replace these seals and the valve cover gasket. The bottom line is that if you see carbon tracking or flashover on a spark plug, the boot or the coil, it is not normal. It is a sign the spark is occurring outside the cylinder. The two causes for the condition around the coil and spark plug could be increased resistance at the gap due to ignition or fuel system problems. Both can be repaired by cleaning out the spark plug well, sealing it if required, and replacing the spark plug and ignition coil boots or the ignition coil where applicable.
Remember when replacing an ignition coil always use a high quality coil such as this Blue Streak UF three, four, nine for late model Nissan and Infinity engines. Blue Streak Import coils are reliable because they are a product of superior design, manufacturing and extensive testing.
This video is sponsored by Standard Motor Products.