I was having the same problem. I replaced my EHA valve and it went away almost 99%. However, once in a while (like 2 out of 50 times) during rains or cold weather, it happens. It use to happen very often before that. So I'm sure there is something else that is respondent to the moisture in the air that somehow works in conjuction with the start but not sure what it is. I replaced all of the fuel flow components prior to that. No change.