All is well except last few times I have been out when I start from cold and set revs at say 1000rpm the revs go up to 2000 and back to stall or almost stall then back up to 2000 then up and down in smaller increments for about 3- 4 minutes all on its own. After it has settled down its fine for the rest of the day.
Any ideas what could be wrong?
Any ideas what could be wrong?