Abstract: An isolator design provides for the isolation of each fuel rail mounting bracket from the intake manifold mounting boss and the screw assembly secures the fuel rail assembly to the intake manifold. The isolator assembly reduces the amount of heat transfer from the hot engine intake manifold to the fuel rail assembly, which in turn transfers heat back to the fuel tank via the fuel return line. The isolation of the fuel rail assembly to the intake manifold is accomplished by an isolator washer placed between the fuel rail mounting bracket and the manifold mounting boss. An isolator sleeve has locking tabs, which snap onto an inside diameter rib on the isolator washer. The mounting screw passes through the isolator washer and isolator sleeve to thereby securely lock each element of the isolator design. The assembly provides a structure for attachment of both isolator parts to the fuel rail mounting bracket.