On July 10, 1995, at 1922 hours Pacific daylight time, a Piper PA-46-350P, N243CV, lost power and collided with a tree short of runway 34L at Van Nuys Airport, Van Nuys, California. The airplane was destroyed. The certificated private pilot/owner received minor injuries. The flight originated at Camarillo Airport, Camarillo, California, about 1800 hours. Visual meteorological conditions prevailed. The pilot said he departed Camarillo airport with both fuel quantity indicators displaying about 30 gallons of fuel in each wing. The pilot had planned to fly direct to the Van Nuys airport and the quantity in one tank was sufficient to complete the flight. Shortly after the takeoff, the pilot changed his mind and elected to fly to Oxnard, California, and accomplish a few practice instrument approaches in preparation for an upcoming airplane instrument rating flight check. After the instrument approach, the pilot flew direct to the Van Nuys airport. The pilot heard the engine skip while turning final after accomplishing the before landing check. The pilot immediately switched the fuel selector valve from the left tank to the right tank. Engine power was not restored. The airplane was examined at the accident site by the Federal Aviation Administration (FAA). The right wing separated as a result of the collision with the tree. About 2 inches of fuel was observed in the separated right wing tank as it laid flat. There was no fuel found in the left wing tank. The pilot indicated in his accident report he failed to switch the fuel selector to the fullest tank during the before landing check.