I few weeks ago I bought a used Poulan 4316. Judging from the condtion of the saw, and in particular, the muffler and bar, it looks at though it is either fairly new or hasn't been used much. It started right up and I have used it for the past few weeks without any problems, until today. Now it won't start. It won't even pop or sputter. I pulled the spark plug and it's in good condition. I checked for spark and it has a strong spark. I cleaned the air filter, filled it with gas, etc. I even poured a little gas down the spark plug hole, and then again down the carb throat. Both times not even a pop. I removed the spark plug again and it was wet and still making sparks. The piston moves freely and looks to be in good shape. With my thumb over the spark plug hole I can tell compression. I don't know how much but with it being warm out I would assume enough to get the thing to sputter. Any ideas what could be wrong with it.