A combination valve for fuel delivery system of a vehicle having an engine, the fuel delivery system being configured to pump fuel to the engine and the fuel delivery system has a regulator for regulating the pressure of the fuel when it is being pumped to the engine by the fuel delivery system, the combination valve comprising: an outer housing defining an inner opening for slidably receiving a body portion of a system pressure relief valve therein, the body portion of the system pressure relief valve defining an inner opening for slidably receiving a body portion of a check valve therein, the body portion of the check valve being configured to provide a first fluid pathway in a first direction when the body portion of the check valve moves from a closed position to an open position as the body portion of the check valve moves in the first direction within the inner opening of the body portion of the system pressure relief valve, the body portion of the system pressure relief valve being configured to provide a second fluid pathway in a second direction when the body portion of the system pressure relief valve moves from a closed position to an open position as the body portion of the system pressure relief valve moves in the second direction within the inner opening of the outer housing, wherein the first direction being opposite to the second direction.