I have been having trouble with my car running out of gas. I am traveling from Houston to Nevada and have run out of gas 4 times with the guage showing 1/3 or less than 1/2 tank. The dealer in San Antonio replaced the Crankshaft Position Sensor and sent me on my way. The dealer in New Mexico coould not identify a problem because I drove it in. A mechanic in Clovis NM (after having it towed in) added gas and sent me on my way. I kept the fuel gauge above 1/2 tank and made my way to Boulder Dam. Because of the grade slope around the dam, the car was pitched forward for several minutes with slow traffic and the car died. I added 5 gallons of gas and the tank registered full and it started up and ran fine into Las Vegas. I am wondering if the tank is bad or sending unit. The two dealers and one independent garage have checked fuel pressure, pumps, relays, and filter and all check out good. I am told that the tank design requires two sending units and the car is good till the second half of the tank is required and the unit on that side is failing? any ideas I am trying to return to my home in Houston soon. thanks, ray