If you bought it recenly and still able to return or exchange at store, try that first. if not, check the fuek lines for hole and leaks, check the fuel filter and clean if necessary. remove the carbuerator and inspect the gasket; it should be soft and flexible, if it seems hard or brittle replace it. clean the carb with carb cleaner sray (available at any local auto parts store) and compressed air. make sure you get inside the small fuel rail holes. if that doesn't work have the carb repaired at a service center or replaced.