So the other day i plugged up my pfc and fired it up. It stayed on and then a few days later when i tried to turn it back on it stumbles and turns off... I didnt change any settings on the pfc... Any suggestions why this is happening???

 

Think we're going to need a few more details on what you mean by stubmles and turns off...
Check your basics:
Are you getting proper fuel?
Are you getting proper air?
Are you getting proper spark?
With supplying those three things, you get combustion at the least and tune it a litter later...