The anti-lock braking system failed on this car. If you would hit a bump in the road while acceleration the car would detect a spinning condition and cause major deceleration being very dangerous when entering a freeway in moderate traffic taking the vehicle from 60+ mph to virtually 40 mph with no warning and no brake lighting to warn approaching traffic. After many visits to Kia dealer remained unaddressed until contacting corporate Kia and finding a posting on Kia Optima forum with another user that had same issue and was finally resolved with some hydraulic part replacement that costs $1,600 and was being avoided by dealers. When I brought this to Kia corporates attention they agreed to replace with that part which did almost resolve that issue except on rare instances car will still hesitate when encountering a bump on acceleration. After that repair however the anti-lock brakes are now failing with erratic pulsing on hard braking and less effective braking.

- Winfield, WV, USA

The contact owns a 2013 Kia Optima. While driving approximately 45 mph, the vehicle failed to stop when the brake pedal was depressed. As a result, the contact rear ended another vehicle. The contact was uninjured. A police report was filed and there were no injuries. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 97,585.

- Sumter, SC, USA

Vehicle: Kia Optima 2013 issue description: If loosing slightly traction (Kia Optima it is very sensitive, all it takes is some dirt on the ground, a little rain, moisture on the pavement, or bumpy road) the system will kill all the engine power between 1 to 2 seconds when you start from a stand still (brings the car to a stop). This makes the car not move and get into dangerous situations when entering an intersections because cars approaching might hit the car. The situation can be repeated once the system releases the power, losing traction again, extending additionally 1 to 2 seconds to this situation. Loosing traction is even easier when the wheels are turned. I opened a ticket on Kia customer affairs (K3229681) once the dealer did not even tested the car with me, and I got the typical answer if they do not have a recall on this subject (it is the way it works) after many calls and visits, I was able to get from the manufacture's Kia customer affairs verbally confirm it is the way should work, immobilizing the car for 1 to 2 seconds. The only solution provided is to disable the tcs which based on the manual disables also the esp. This issue has been reported by other owners on multiple forums, and no other car I drove works in that way, not even my Hyundai sonata 2013 which is the same car but with different body. Mode information on the attached document.

- Alpharetta, GA, USA

My 2013 Kia Optima's brake and gas pedal will vibrate/grind while driving in wet conditions. It started the day I bought it. While I was signing papers, it started to rain. During the drive home (immediately) I noticed vibrations through the pedal. I asked about it and they stated it was normal. Since it did it immediately, now I see similar complaints and no longer think I am crazy. I have had this vehicle since October 2013 and the issue persists also my backup camera sometimes does not engage. A few times the radio system gets stuck on stupid (wont turn on), but this only happens when the back up camera has issues. And this week 7/2015 my jukebox stopped working properly. Luckily, I found the reset switch near the volume control and it works again :) MA 10/8 updated 3/22/2016

- Worthington, OH, USA

My 2013 Kia Optima ex brake will vibrate/grind extremely bad under my foot. The car brake does this every time I am driving in wet conditions. The first time, which was about 2 weeks after getting my car, was after I had it washed. It also does it while driving in wet road conditions. I contacted Kia at the first occurrence and was told it was my ABS system, followed by a description of what that means and it's function. However, I know this is not normal ABS performance, as would any other driver. Not only does this malfunction distract my attention when it happens, it contradicts the purpose of ABS! it scares me when it is happening, enough for me to loose Focus. This has been happening for approximately 28 months so far.

- Chatsworth, GA, USA

I was driving down a moderately steep slope and when I applied the breaks to make a right turn I could feel a shaking on the break petal about a 20 second duration. This has happened twice. Both when I was driving and my wife was driving.

- Pinson, AL, USA

I was driving my car down a hill, I had the right of way so I did not need to engage my brakes at a stop light at the bottom of the hill. The emergency parking brakes automatically engaged for no apparent reason. I could have easily been hit because of this malfunction. I had to pull over in a parking lot and before I could park the car, it completely locked up as pulled in. I was forced to stop in this middle of a narrow parking lot blocking cars from being able to exit their spots. I called Kia roadaide assistance, who instead of getting me help, transfered me to a local dealer who was unable to provide any help. Not only did my car fail me, Kia cusotmer service did as well..

- Mclean, VA, USA

Vehicle in reverse backing up on steep driveway, foot on fuel pedal, car began its automated hill holding function, while in reverse, heard high RPM, transmission was slipping into neutral, car began rolling forward, put foot on brake, brake failed, car accelerated rapidly, and engine died, then hit the wall inside the garage. I estimated, speed at time of impact approximately 10 to 15 mph. Noticed another entry filed similar to this, had same fuel, brake fail symptoms.

- Howard, OH, USA

The front brakes on this vehicle lock up really easily on slick roads, they are extremely dangerous. I took my vehicle to the dealer but they claimed they were operating to specifications for the Optima. I'm speculating, but they appear to work as though some engineer set them up to work on roads that don't have ice or snow on them, not really understanding or realizing that we have ice and snow on our roads, here in the usa. I don't know where this vehicle was designed or engineered, but it really appears to me that ice and snow covered roads were not accommodated for. I think they are extremely dangerous and have a great deal of difficulty stopping the vehicle on icy, or snow covered roads safely and without the front wheels skidding out of control. The anti-lock feature does release them but as soon as they apply again they go into a skid.

- Greendale, WI, USA