Fouled Plugs

[MRTOOTH]

Hey Guys,

I have a mostly stock 75' 280Z. Last year I changed my plugs and put in splitfire plugs. Last month i took them out to see how the condition was and i noticed that they were a little fouled. I sandblasted them and put them back in, the car was still running fine. Now a month later the car is idling a little rough, so I decided to check the plugs, when I took them out they were covered in oil. I have not idea what's going on, can anyone help?

[MikeW]

Hey Guys,

I have a mostly stock 75' 280Z. Last year I changed my plugs and put in splitfire plugs. Last month i took them out to see how the condition was and i noticed that they were a little fouled. I sandblasted them and put them back in, the car was still running fine. Now a month later the car is idling a little rough, so I decided to check the plugs, when I took them out they were covered in oil. I have not idea what's going on, can anyone help?

Is the car burning oil? If the plugs are fouled with oil then it's either coming past the rings or through the valve guides. A compression test can help you determine which is the source of the oil.