I just discovered the same problem after having an emergency room visit, doctors visits, inhalers and what was thought to be an unexplainable start of Asthma. I'm surprised there aren't more recent posts on this subject. I had the evaporator core replaced (with the new improved that won't flake), the ducts and vents cleaned and the carpets shampooed. It's been 2 weeks and I haven't had the breathing problem I was having. Just wondering if anyone sent medical bills to Lexus to be reimbursed for expenses incurred due to this problem? Lexus is very aware of this problem but says it only happens in some cars.