My ESC & check engine light come on and car stalls and shuts off while driving on streets and the freeway.

- Royal Oak, MI, USA

While driving the car at a rate of 30 to 40 mph, I felt a jerk in the engine or transmission speed of my vehicle, and afterwords noticed my ESC off light and engine lights had been illuminated and unable to be shut off with my ESC switch. I also noticed that I was unable to rev my engine past 3000rpm's, consequently affecting my vehicle's usable power band and rendering me(the driver) unable to control the car's overall speed. After turning my vehicle off and then back on, the problem would go away, but only temporarily until I was again driving. I then went to a mechanic to have my car's computer scanned and found that there was a problem with my crankshaft or crankshaft sensor. My computer was then reset, but the problems persisted again shortly after.

- Myrtle Beach, SC, USA

There is a transmission problem with Hyundai Sonata 2009, anytime the car is accelerated the transmission box gets stuck which could lead to safety hazards.

- Troy, MI, USA

Ignition switch engages starter when turning engine off. On several occasions, engine started on its own when key was in accessory position.

- Grand Junction, CO, USA

The front valve cover gasket leaked oil down to my alternator, causing it to malfunction and making my transmission shift awkwardly.

- Mobile, AL, USA

After I start my car and drive it for less than one mile, my car will stall when I take my foot off of the gas pedal to slow down or stop. This usually happens when I slow/stop the car for the first time after starting.

- Poland, OH, USA

Taking my car for the first oil change since I bought it and the car stalled while in neutral waiting for an oil change. Restarted without a problem. It has also tried to stall while driving several times since, more frequent than before. It's also stalled in stop and go traffic. My check light only comes on for a split second when the car tries to die, but after that, it's just fine. Brought it to 3 dealerships that told me that nothing was wrong with my car. I bought an obdii scanner and found trouble codes P0335 and P0108. Took it to the dealer again and they still couldn't find a code. My car has almost stalled while trying to cross a busy intersection and no one wants to even try to help me.

- Houston, TX, USA

Please be advised that I purchased said vehicle new and at around 35000 miles I started to notice that when I slowed down and came to a stop the transmission would jerk on the down shift, which is not normal. On 01-19-2012 I brought my car to the dealer where I purchased from. I was informed that this problem is common and that once my computer is reset it should go away, and there is a service bulletin on that issue. On 03-19-2012 I was having the same issue so the transmission was replaced with factory reconditioned transmission. Now with 74000 mile the car is back for the 5 th time for the same transmission problem. The dealer has my car and I have not heard from the dealer or Hyundai corporation for two weeks. I believe that Hyundai corporation knew the problem existed and neglected to fix the problem other wise a new car with 35000 miles should not have this problem and the mechanics don't know how to remedy the faulty transmission. I am very disappointed with Hyundai and there handling of this problem. I believe the damage has been done, and new software is not going to fix this problem, the bands in the transmission are worn now, the damage has been done. This is just putting a band aid on a serious problem and a manufacturing defect. One does not anticipate any serious problems with a brand new car with only 35000 miles. What good is a 10 year 100.000 mile warranty when you start having these problem at 35000 miles. I have done some research on-line and there are others who have the same problem with same car, I am not the only one.this is a disgrace Hyundai corporation I purchased said vehicle from atlantic Hyundai Inc. Located at 193-205 sunrise highway, West islip NY 11795. I have also contacted Hyundai corporation several times but to no avail.

- Deer Park, NY, USA

The contact owns a 2009 Hyundai Sonata. The contact stated that the key was in the ignition when she exited the vehicle and the doors erroneously locked. The contact also mentioned that the chrome on the passenger's side front door handle was peeling and tore through the contact's hand. Additionally, the steering wheel failed to lock and the vehicle jerked abnormally when shifting down. The vehicle was taken to the dealer, who stated that the door lock and jerking failure could not be diagnosed and the starter lever needed to be replaced. The vehicle was repaired. The manufacturer was contacted about the failures. The failure mileage was approximately 82,000.

- Deltona, FL, USA

The vehicle was aqua planning, the driver lost a complete control over the vehicle. The car was bouncing between road sides, left and right - 3 times. The car hit the gate rails 3 times. None of the air bags came out and the seat belts appeared not to be locked at the moment of accident. As a result the passenger's body moved freely in the car and hit the left rib and internal organs, and hit the right side of the face, including cheek bone and nose. The passenger's face was severely bruised and swollen. Besides, both driver and passenger had a whiplash.

- Louisville, KY, USA

While slowing at around 25-30 mph the car would "jerk" forcefully like a sudden stop. This happened every day. It would improve as it warmed up. I took it to the dealership and was given excuses (they told me that the transmission needed flushed-at my expense, my driving habits, etc). Finally after several trips to the service department, they admitted the issue. The transmission was eventually replaced after they "reset" and flushed the original transmission. It seemed to get better. I still feel the "jerk" in the downshift, but it is not as bad as it was. I mentioned this to the dealership and they told me that it was going to cost $100 just for them to "look at it" even though it is still under warranty.

- Grand Bay, AL, USA