I own a 2020 Sorento with a 3.5-liter MPI engine and 8-speed automatic transmission, runs on gasoline. I noticed a situation in my car in recent days, when I press the brake pedal to reduce the speed of the car, the car keeps slowing even when I take my foot off the pedal. Sometimes I even need to press the gas pedal to get it back in motion. This situation doesn't happen often but it does happen some times when I'm driving. I checked the flanges and brake pads visually and they looked good to me, there are no scratches or tears on the flanges and the brake pads are still quite thick. I applied the brake pedal check when the car is on and off. There is a difference in the amount of brake pedal drop, as it is more flexible when the car is running. Do you have any suggestions to ascertain the cause of the malfunction?
Best regards and thanks.
Check to booster vacuum hose running from the intake manifold to the booster for cracks and separation.