I had the same problem and figured something out. I don't have a choke and it does that same thing every time the engine is cold. All I have to do is cover the air intake most of the way...Eventually after it gets warm you can just drive off and it works like a million bucks. I have to go about 6 blocks putting my hand over the hole and releasing and vice versa, But it's damn worth it when she starts going. I'd bet thats your problem anyways try it once.