After the car has sat idle for several hours when I depress the brake pedal to start the car I get a whoooomp sound. I took the car to the dealer and was told that after the car sits idle for awhile the air goes out of the breaking system and therefore it makes this sound at start up. My question are why, after two years of ownership, is it happening now" and, why isn't the part allowing air to escape replaced"

- Tampa, FL, USA

9/14 vehicle parking breaks engaged. Replaced parking break sensor and motor and car was available to be picked up on 9/21, but not picked up until 9/24. On 9/25 parking break engaged again doing roughly 15mph after turning the vehicle on in a parking lot.

- Reston, VA, USA

While driving in a parking lot, the parking break automatically engaged. Approx speed was 15 mph. Repairs still being worked after 5 days. Unknown root cause. Attempting to replace the motor next.

- Reston, VA, USA

There is noise pooook sound when I press the brake pedal. It come from the breaking system. My car has only 13467 miles on it.this sound comes once when I press brake pedal. I hear the noise when the vehicle is between 10- 40 mile per hour speed. Took it to sacramento Hyundai found the defect still in garage. Also when press the brake pedal slow release of the break.

- Sacramento, CA, USA

New Sonata hybrid, owned 3 months, mileage 6,000 miles. Right rear brakes have locked on two different occasions at low speed while negotiating a hard left turn on a state highway. Both failures occurred at the same highway location about a month apart. When the right rear brakes locked, the vehicle was hard to control and as I was negotiating a sharp turn on a mountain road, it was terrifying. If there had been other vehicles coming in the opposing lane, there very easily could have been a head-on collision or worse (I.e car over the side of the mountain). Car will be taken to dealer for analysis and repair.

- Signal Mountain, TN, USA