Small Engines (Lawn Mowers, etc.): Grasscutter dies giving gas., ryobi bc30, grass cutter

Question
I gad a problem getting my Ryobi BC30 grass cutter to start. Now that I solved that problem, it starts, but when I give gas, it dies down. If I release the throttle lever, it will remain running. As soon as I give gas again it will die again.

I cleaned the carburetor, gas tank, changed the gas lines. Cleaned the filter in the tank etc. Put in a new spark plug.

Answer
After assuming your running a fresh correctly mixed oil/fuel mix. You need to remove the muffler and check if there is a spark arrest screen in that system, if so it may be carbon build up needing cleaning, or the muffler itself could be blocked, usually from running a oily mix. I am also assuming the mixture screws on the carburetor have not been tampered with yet either.  

ALSO make sure you have the lines in the correct place after replacing them!