On September 20, 1998, at 0745 hours Pacific daylight time, a Piper PA-28-140, N5817U, experienced a loss of engine power after takeoff and impacted terrain near the Dayton Valley Airpark, Dayton, Nevada. The aircraft, operated by the pilot under 14 CFR Part 91, sustained substantial damage. The private pilot and one passenger, the sole occupants, were not injured. Visual meteorological conditions existed for the personal cross-country flight and no flight plan was filed. The flight was scheduled to terminate at the Klamath Falls, Oregon, airport. The pilot stated that he and his wife had flown from Oregon to New Mexico where they had spent the week flying and camping. No discrepancies were noted with the airplane during the trip. The day before the accident they had flown to the Dayton airport and spent the night. The pilot stated that he had to refuel the aircraft with auto fuel from a local gas station, as there were no fuel services located at the airport. He stated that the aircraft was approved by the Federal Aviation Administration (FAA) for auto fuel consumption with Supplemental Type Certificate (STC) SA 1963 GE. The terms of the STC require the pilot/operator to determine that the automotive fuel meets certain specifications prior to use. The pilot stated that auto fuel has been used in the aircraft on prior occasions without difficulty. On the morning of the accident, he stated that he conducted an engine run-up per manufacturer's checklist with no anomalies noted. The pilot stated that he leaned the mixture for the high altitude takeoff and the aircraft was halfway down the runway when he lifted off. The pilot reported that the engine was running with no noted discrepancies. At the departure end of the runway, the engine stopped. The pilot stated that the engine did not cough or sputter, but the rpm's dropped and the engine was very quiet. He stated that he turned the aircraft to the left, and made an unsuccessful attempt to restart the engine with the throttle and mixture full forward. The pilot stated that he set up for an emergency landing and collided with sagebrush off the airport. Witnesses to the accident stated that the aircraft appeared to be "laboring" at full power, but with low airspeed and did not appear to be climbing. The airframe and engine were examined by an investigator from the Safety Board following recovery, and included an engine run, and general and fuel system inspections. The throttle cable was restricted due to damage to the engine during the accident sequence. The spark plugs were inspected, and according to Champion's Aviation Check-A-Plug chart were carbon fouled. Aviation gasoline, grade 100LL, was put into a fuel tank and plumbed into the aircraft fuel lines at the wing root fitting. Using the aircraft systems, the engine was started. During this initial engine run at 1000 rpm's, the engine was rough. On the second engine run at 1700 rpm's, the engine ran with no discrepancies. There was a 50-rpm drop on the magneto check, which is in manufacturer limits. The engine and fuel system was inspected with no discrepancies noted. The carburetor was damaged and could not be tested; however, no discrepancies were noted with the components. A fuel sample removed from the aircraft tanks during disassembly was retained by the recovery company and found to be a bright yellow color mixed with blue. According to the carburetor icing probability chart, conditions at the time of the accident were conducive to serious icing during cruise or climb power.