I'm trying to diagnose a chainsaw to figure out where to start irt fixing it. The basic issue is that it starts but wants to die pretty easy. There's a "sweet spot" with the trigger that generally keeps it running but when you pull the trigger close to max pwr the engine loses pwr and will die if I don't release the trigger a bit. I was planning on starting with a new fuel filter? Does it sound like the symptoms of a bad fuel filter or is there something else you would suspect? Thanks