

What does this plug tell about the inside operation of the engine? I can't find any plug that looks like this in any online charts.


What does this plug tell about the inside operation of the engine? I can't find any plug that looks like this in any online charts.
Next time make a picture before you cleaned and sanded the plug, the color of the electrode can tell a lot about operating conditions.
To answer your question: it looks a bit fouled with oily deposits, so its possible the engine is running too rich.