I have an 07 Tahoe LT, has 180k miles and has had trouble starting for a while. The thing is though if I go to start it right in the morning or after not driving it for a while (2-3 hours) it'll start right up, but if I go to a gas station and fill up and try to start it, it won't go. I think it's a security thing because it'll crank just fine but it doesn't seem like it's getting fuel. The key for the ignition is slightly bent so I'm wondering if that might be the reason. Also it'll start if you drain the battery then jump it.