An anti-dribble valve is a component of a system used for diesel engines. Its main function is to provide precise timing of fuel injection, particularly at the end of the injection time. If fuel was allowed to 'dribble' after the main phase of injection, this fuel would be too late for good combustion and so would be only partially burned as visible exhaust soot. Although simple, the valve has several functions: * A one-way check valve * A 'pop' valve * An anti-dribble valve The valve was introduced on injection equipment by the firm of CAV Bosch in the 1930s.