If you're pulling out the choke and it's running faster, then you definitely have carb issues, the jets need a thorough cleaning. I just did a lawnmower for a lady a couple doors down, run for 2-3 seconds and quit, over and over. Pulled off the bowl and it was full of little gummed up gas balls. Took out the main jet, ran a very thin piece of copper wire through it and pushed out more jello gas. A little more cleaning, put it back together and it runs like new. She even said she used stabilizer regularly. I showed her the can of Seafoam for future use.