I finally took my car back to the car repair place today. They didn't keep me waiting in the waiting room all day this time, but they didn't fix anything, either. They told me that the problem is being reported by the fuel sensor, and that the problem may or may not be with the fuel sensor itself, but that either way, they don't know how to fix it for me - I have to take it to the dealer for that. Bah. I used to take it to the dealer whenever I needed anything fixed, back before the warranty expired, but it appears I should continue doing so now, even though the dealer is inconveniently far away. Taking it anywhere else doesn't get anything fixed.