If it bogs or hesitates going into the secondaries like you describe, it surely could be. Do you know how to limit the door's opening? There is a "tang" cut into the secondary door on the driver's side. There is a stationery tang on that side as well. You may also need to adjust the spring tension, too. It's usually a juggle between the two. Here is how to adjust the air door opening. See the bent tang on the door the red arrow is pointing to? That's how to adjust how far the door opens and make changes in the secondary overall mixture. You "may" need to bend yours so that it doesn't open as far as the door in this picture. You just need to kinda play around with it. Maybe adjust the door "a little" less open. Drive it. Come back and tighten the spring a little. Drive it. Rinse and repeat. Do you have the secondary spring adjusting tool?