uneven sooting of plugs

[Figment]

Should I be concerned that my #1 and #4 plugs are covered in oily black soot, but #2 and #3 are dry and clean?

[Don Moyer]

The fact that the plugs in cylinders one and four are oily is of some concern, since oiliness usually means the cylinders are not firing. I recommend that you check the compression (a thumb check is sufficient), and also that you feel the plugs after running for a few minutes. If the plugs remain cold to the touch, it would be an indication that they are not firing.


Don