If your plugs are fouled, it means that they have a lot of carbon built up on the electrode. As gas burns in the cylinder, it leaves carbon that over time, builds up on the plugs. It's normal and nothing a good tuneup won't fix.
oxygen sensor
old gas or fuel mixture needs adjusting
Fouls
NGK number CR9E If your engine fouls plugs on a regular basis, the next step hotter plug, CR8E may help the plugs last longer.
It means the % of fouls there are in a game
The singular form of fouls is fouls.
It means if your team gets 4 fouls in a quarter then you will shoot 2 free throws the rest of the fouls
2 technical fouls and 6 fouls
Team fouls are the total fouls that all the players together committed. Personal fouls are each player individually.
over 600 fouls
In most leagues it is 5 fouls until you are out. However, in some tournaments they can make up whatever rules they want so any number of fouls. But basically it is 5 fouls. -Kristen (I have played basketball for 6 years)
Check your premix ratio, carb jetting and make sure you are running the right spark plug.