I have seen this. A quick tap of the pedal helps, which told me that air flow was off. I adjusted that with an allen wrench through that hole in the air filter housing. Don't adjust much, keep a log of your turns, like 1/8 CCW drive and see how it starts next time. I just drove around oveer my normal course for a few days with the tool handy and kept adjusting until I hit the sweet spot. You have to push past the spring load to engage and cause an effect to the baffle position.

I have diagram at home if you need it. some one here can probably get this to you faster.