Q: When heat is on outside air, exhaust smell. Not when circulating air. Worse when standing behind other cars.

Hello, thank you for writing in. The vehicle is designed to pull in the air in from around the vehicle to use in heating the air. When on that setting, the engine is pulling in exhaust fumes. This means that the vehicle has an exhaust leak. The leak will need to be found and repaired before the smell will go away. Keep in mind inhaling these fumes is not good as they are toxic. You will want to keep the heating and air conditioning system on recirculate. When you are at a stop and idling, the smell can accumulate because there is less airflow to push the fumes away from the cabin. Finding these exhaust leaks can be done several ways, but repairing them can be difficult. For more help contact our service department.