What would cause the spark plugs to foul out on a 1994 ford explorer limited?

Answer 1

Spark Plug Fouling

Although there are probably other causes that I can't think of at the moment, there usually are two main causes of spark plug fouling:

• The engine is worn, and loose fitting parts [like the "oil" rings on the pistons] that allow engine lubricating oil to get into the combustion chambers [cylinders]. The oil then gets onto the spark plugs, and is "cooked" on.
• Another possibility is that the fuel mixture is way too "rich," causing incomplete combustion which deposits carbon and lacquer on the plug tip.