The contact owns a 2015 Ford Explorer. The contact stated while driving at approximately 60 MPH, there was a strong abnormal odor intermittently coming from the inside of the vehicle. The failure occurred on several different occasions. The contact stated that it became difficult to breathe; there was no medical attention sought. No warning light was illuminated. The vehicle was taken back to the place of residence. A dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 76,000.