* Check Gas and Oil: Sometimes there may be a low oil sensor, or there may not be enough fuel in the tank or there may be an air bubble in the fuel line. Fill the tank at least 3/4 full with fresh gas.
* Disconnect the fuel line at the carb or intake (EFI) and check for a strong fuel flow.
* Water is in Gas Tank: If your engine has water in the gasoline, it will start, run for a few seconds, then the engine will die. You can look at the bottom of the gas tank to see water beading if it is present.
* Loose Spark plug wire
* Clogged or wet air filter
* Faulty stop switch or connection
* Throttle cable is grounding to the engine stop terminal