I have a Poulan Weedeater Featherlite Plus that will not continue to run. It seems as though the tank gets pressurized and when I open the gas cap there is a surge of air into the tank. I don't know if this is supposed to happen or not. There are 2 tubes into the gas tank from the carburetor. One is short and the other goes clear to the bottom of the tank and into the gas. I can pour gas into the carburetor and it will start and run for 5 seconds or so at full power then just dies out. HELP!!

The short tube vents the carb and tank to allow easy flow of the fuel. The longer tube is your supply and usually has a clunker on the end so the fuel supply is uninterrupted when the eater is moved into different positions. Check to see that the clunker is still in place.

I'm betting that the vent in the gas cap is plugged. Shoot carb cleaner through the vent hole on the outside of the capand then blow it out with compressed air through the through the same hole. Should clean it right out. If not, try soaking it for a while in the cleaner and then blowing it out. The little filter in the cap is made of sintered bronze, so the cleaner won't hurt it. That short fuel line in the tank is only a fuel return, not a vent. Your problem IS the cap vent being plugged.