Some 2021-2023 Bronco Sport vehicles equipped with a 1.5L engine built on 24-Jul-2021 and through 31-Aug-2023 may exhibit a hissing noise from rear liftgate area when driving straight between 35-50 MPH (56 80 Km/h). This may be due to the absence of the rear floor insulator located in the spare tire compartment. To correct this condition, follow the Service Procedure to install a rear floor insulator in the spare tire compartment.
