I HAVE A 2018 FORD FLEX WITH 900 MILES ON IT . I TOOK MY FIRST ROAD TRIP IN 8-4-2018 AND WHILE ACCELERATING HARD TO GET ONTO THE INTERSTATE I NOTICED EXHAUST FUMES WERE COMING INTO THE CABIN AT AN ALARMING RATE , I HAD TO SLOW DOWN AND ROLL THE WINDOWS DOWN IT GOT SO BAD,MY EYES WERE BURNING ,FELT SICK AND MY CHEST FELT FUNNY. I TRIED IT SEVERAL MORE TIME WITH THE SAME RESULTS. IT SEEMS LIKE IT HAPPENS WORSE WHEN I HAVE MAX AIR ON. NORMAL CITY DRIVING I DON'T NOTICE IT. I CAN'T TELL IF IT IS COMING THRU THE VENTS OR THE SEAL ON THE BACK DOOR.