When I go to start this truck, either cold or hot, if I give it throttle, all is fine. If I don't press the throttle, sometimes it starts just fine, others it starts with a lope. when it does that if I give it throttle it clears up and runs well. If I don't goose it it will dwindle down and die. Since it is not a constant problem it is hard to figure out. Anyone ever have anything like this?