Contaminants that end up in engine oil form soot, varnish, and sludge, which all can damage the engine and affect its performance. Sources of these contaminants include blow-by gases from combustion and volatiles in the crankcase that are vented into the engine as an antipollution measure. New products from DSM are especially effective against soot, which are hydrocarbon fragments that contain oxygen and sulfur. Soot tends to agglomerate and combine with polar compounds in the oil, and is commonly found in the combustion chamber.
