Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2012 Kia Optima owners, lightly cleaned up (personal details are redacted by NHTSA).
While in park and driving the instrument panel will show, "Check Brake" and "Hybrid System Warning! Safely Stop and Do not Drive". This is accompanied by the engine not responding to the gas pedal. The brake pedal will also loose pressure and once pushed the brakes will lock up making a grinding noise. The problem has not been able to be duplicated by the dealer. However there are multiple forms and online communities dedicated to try to resolve this issue since it's so prevalent. This issue causes a major saftey hazard as the car comes to a grinding halt and does not respond to the driver. From online sources it seems the problem is prevalent across years and models and only tied to hybrid vehicles.
Because the brake stopper or brake switch are messed up and my brake tail light stays on all night causing it to drain the battery If the car is braking while I'm driving it and the traction control light comes on and the speed is decreasing as I'm driving because the car is braking on it's own it has nothing to do with the lights Nor the battery the root of the issue is the brake line because the tail light will not cut off because the brakes are still engaged even when the car is off causing the tail lights to stay on so the lights is what is draining the battery the lights stay on all night in a car the battery dies but the battery nor the lights is the issue it's the brakes
When the brake pedal is pressed on the brakes will grab. It snatches the car kinda hard. Also when you give the car gas it will hesitate and will not accelerate. Another with the gas is that you can be driving at a higher speed such as 45 to 55 or so and you press down the gas pedal like your going into passing gear and it will not accelerate it's like it's trying to stop. Feels like the car is gonna fall on down onto itself and it loses power.
Here I explain the problem better, when the car is at a low speed, such as when parking, the gasoline engine starts and it starts to rev up to 6k RPM and after that it brakes and hits hard, this would be dangerous on the highway and another problem is that when accelerating it has a delay of 1-3 seconds, and I want to report this problem to see if there is any solution
Tl* the contact owns a 2012 Kia Optima. While driving approximately 5 MPH, the vehicle suddenly accelerated independently and crashed into the median. The vehicle was towed to the dealer for diagnostic testing where the technician advised that the front passenger side tire and axle would have to be replaced. The failure recurred four times. The fourth time the failure recurred, the contact crashed into another vehicle. The contact sustained injuries to his right knee. The front passenger sustained injuries to the neck, back and right arm. The rear passenger sustained injuries to the right leg. The passengers were transported to the hospital via ambulance. The driver sought medical attention on his own after the crash. The police reported to the scene and a report was filed. The vehicle was towed to the dealer. The vehicle was taken to an auto body shop for the body damage repair. …
'Takata recall' I'm currently buying a Kia Optima 2012 and everything was working fine and had maintenance up to date at Kia of orange. Then I did full service which I payed 600$ or so and after the car started giving me problems, I went to my friends house and my boyfriend got off to get tools from the house it took him ten minutes to come back. The car was on and I was windows up and ac on when he came out he saw fire under the front left light. It got on fire and we were scare for our life's and we manage to run around and find anything that will help we had water and it wouldn't turn off, we didn't know it was electrical so it was melting plastic until we manage to find a fire extinguisher while I was calling 911 we thought the car was going to blow up. Second of all we fix it insurance cover. We call Kia they told us our insurance had to pay it. …
Issue started 2 months ago. Noticed that vehicle acceleration is sluggish. Sometimes I have to take foot off the acceleration pedal then depress it again in order for vehicle to accelerate. Acceleration is unreliable and dangerous. Electronic stability sensor also started lighting up and cruise control became inoperable. Also noticed that my tail lights lit up on its own (and did not turn off) while vehicle is parked and fob not near vehicle, draining the battery. Police came by in the middle of the night to report that my tail lights were on. Tail light did not turn off when pressing the fob unlock/lock button. Had to restart the engine, drive around the block then turn off engine before the tail lights came off... But it turned back on again on its own that same night (in the middle of the night) and had to repeat the process. My battery was drained and had to replace it 3 days ago. …
I have a 2012 Kia Optima hybrid at 80,[redacted], and have always kept up with the scheduled services/maintenance. I barely drive my car nowadays, and just ride my bicycle to take public transportation that is 1-mile away. My wife and I were driving on the freeway, going 65mph, 47-miles into our drive, our car started jerking. We have about 3-4 miles left to our destination. When you pressed on the gas, it sounded like it was just accelerating and not shifting to the next gear. There were no warning lights or notification as to why that was happening. We exited from the freeway and stopped at a local plaza to try and reset the car, and gave the car about 20-mins before driving again. When we tried driving about the last 10-mins, even at 20mph, it was still jerking and still sounded like it wasn't shifting to the next gear, and still no warning lights. …
Vehicle's ABS brake activate randomly illuminating the ABS brake signal on dashboard,while in motion and without touching the brakes. This causes the vehicle to decelerate and has made the vehicle come to a near complete stop. Even if the gas pedal is pressed to accelerate the vehicle will not increase speed, only decrease. The issue happens 8/10 times while making turns and approx 5/10 while driving straight on freeway . This happened on 11/08/2019 in the evening, I immediately took my vehicle back to Kia and they claimed to have driven my car for 20 miles and didn't see or experience any issues. My car is a 2012 and only has 58, 388 miles. I demanded they keep looking but they caught an attitude like I made the scenario up and any stated that I should drive the car with their mechanic as they "cannot replicate my driving", like I'm driving in the [redacted] indy 500. …
Tl* the contact owns a 2012 Kia Optima. While driving downhill with the brake pedal depressed, the vehicle abruptly accelerated. There were no warning indicators illuminated. The contact was able to engage the emergency brake, but the vehicle decelerated and returned to normal after the accelerator pedal was applied with caution. The vehicle was not taken to a dealer or local mechanic for diagnostic testing. The manufacturer was not notified. The failure mileage was 23,538. Updated 10/25/17 consumer stated: while driving down hill, with brake pedal depressed, getting ready to stop at stop sign, the vehicle accelerated unexpectedly to a speed of 30 to 35 MPH. I did not engage the emergency brake. I did shift the vehicle from drive to neutral. Engine continued to race uncontrollably. I tapped the accelerator pedal with my foot at which time the engine returned to normal. …
NHTSA investigations
Throttle control system vulnerabilities
The Office of Defects Investigation (ODI) of the National Highway Traffic Safety Administration (NHTSA) received a petition letter dated October 10, 2021, requesting an investigation of possible defects in the electronic throttle control (ETC) system on certain Kia vehicles resulting in the opening of DP21-003.
Acceleration complaints in other Optima years
Frequently asked questions
How common are acceleration problems on the 2012 Kia Optima?
NHTSA has 40 complaints about the speed control & acceleration of the 2012 Kia Optima, 4% of the model year's 920 complaints.
Is there a recall for 2012 Kia Optima acceleration problems?
No. NHTSA lists no speed control & acceleration recall for the 2012 Kia Optima, though it has 5 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2012 Kia Optima acceleration problems start?
Half of the complaints with a recorded mileage happened before about 74,000 miles, and 26% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 2 fires and 3 injuries to speed control & acceleration problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.