First time when I drove my MDX from dealer, it was pulling to left. Dealer tried to fix the problem by changing the alignment values here and there and rotated brand new tires. Now there is no drastic pull to one side but here is my concern: when I leave the steering wheel, it goes to either left or right. Also I feel some stiffness at the steering. Acura Mechanic told me that according to Honda specification, if the car drifts to next lane in 6 sec then only they treat it as a problem. In this situation what should I do? Can I talk/email directly Acura about this? What are my options?