GS300_TT

I have this identical problem, but I don't think it's a fuel gauge sending unit problem. Sure, my car runs out of gas at 1/8th tank, sometimes within 2-3 miles of the warning light coming on, and sometimes even before the warning light comes on. But here's the strange thing, the tank is a 19gal tank and I'm running out of gas when I've used ~14gal of gas. I rarely pumped more than 15 gallons into my car, yet it's got a 19gal tank. Over the last couple years I've been filling up at 1/4 tank because it's getting worse, but I'm usually pumping 12 to 13gal of gas. So the sending unit seems accurate. For some strange reason my car starts bucking and spitting, like I'm running out of gas around 1/8 tank, or about 13gal down. After I fill up the car runs OK. So I'm wondering if anyone else has pumped more than 15Gal into their 1998 Lexus GS300. I'm wondering if the 19gal spec in my manual is a misprint, of if my fuel system has a problem, like maybe something in the tank blocking flow, or an air leak in the pickup, etc. I would expect this car should go another 50mi AFTER the warning light comes on, like other cars. If I "space out" and see my gas warning light come on, I'm at the next station IMMEDIATELY because I know I'm terminal if I don't. My light is more like a 1mi warning light, if that.

The GS300 has a saddle tank with a hump in it where the drive shaft passes through. It sound like the fuel from the passenger side of the take is not being transfered over to the side that has the fuel pump in it. A simple test would be the next time you run out of fuel remove the back seat and then the fuel sending unit from under the passenger side rear seat. If you see a lot of fuel then it is not transferring. There is a tube that comes from the passenger side to the fuel pump assembly on the drivers side. A device on the fuel pump assembly creates suction to bring the fuel across. If this device is broken or the line is kinked it will not work.

Ben