Actually, I understand where Nitro Rustler Racer is coming from. He is not talking about the few seconds that your engine runs lean when your engine doesn't get gas. He is referring to when the engine runs lean for about the last minute of your run, just before it runs out of fuel. You can usually tell when the truck is running low on fuel, because it will begin to stutter and the engine wants to cut out. This is the leaning he is referring to, not the few seconds when you shut the truck off.