At about 22:15 Pacific time, a Cessna 172C lost engine power during an attempted go-around and crashed off the departure end of the runway at Corona Municipal Airport. The three occupants were not injured. The student pilot, who owned the airplane, said he switched the fuel selector to the BOTH position about 5,500 feet over Ontario, verifying its position by feel. On short final he noted that they were too high and too fast, so he initiated a go-around. The engine did not respond to a power application. Witnesses who arrived on the scene immediately noted there was fuel in both tanks. Investigators later found the fuel line to the gascolator was broken at the attach point (possibly from impact), the left fuel tank was empty, and the right fuel tank contained fuel. The fuel selector handle was free spinning in its assembly. The unit that houses the fuel selector was removed from the floorboard and the fuel selector valve position was observed to be on the left tank. The spark plugs were consistent with lead fouled operation. The carburetor bowl was found empty. In addition, conditions were conducive to serious carb icing, even with climb power.